Update contributing guide, make PR template, move github assets

ISSUE_TEMPLATE → .github/ISSUE_TEMPLATE.md

 (Are you asking for help with using Caddy? Please use our forum instead: https://caddy.community. If you are filing a bug report, please take a few minutes to carefully answer the following questions. If your issue is not a bug report, you do not need to use this template. Thanks!)
 
-### 1. What version of Caddy are you running (`caddy -version`)?
+### 1. What version of Caddy are you using (`caddy -version`)?
 
 
 ### 2. What are you trying to do?
@@ -8,7 +8,7 @@
 
 ### 3. What is your entire Caddyfile?
 ```text
-(Put Caddyfile here)
+(paste Caddyfile here)
 ```
 
 ### 4. How did you run Caddy (give the full command and describe the execution environment)?
@@ -27,4 +27,4 @@
 
 ### 8. How can someone who is starting from scratch reproduce the bug as minimally as possible?
 
-(Please strip away any extra infrastructure such as containers, reverse proxies, upstream apps, dependencies, etc, to prove this is a bug in Caddy and not an external misconfiguration. Your chances of getting this bug fixed go way up the easier it is to replicate. Thank you!)
+(Please strip away any extra infrastructure such as containers, reverse proxies, upstream apps, caches, dependencies, etc, to prove this is a bug in Caddy and not an external misconfiguration. Your chances of getting this bug fixed go way up the easier it is to replicate. Thank you!)

.github/PULL_REQUEST_TEMPLATE.md

+(Thank you for contributing to Caddy! Please fill this out to help us make the most of your pull request.)
+
+### 1. What issue(s) is this pull request related to?
+
+
+### 2. What does this change do, exactly?
+
+
+### 3. What documentation changes (if any) go along with this PR?
+
+
+### 4. Checklist
+
+- [ ] I have written tests and verified that they fail without my change
+- [ ] I have squashed any insignificant commits
+- [ ] This change has comments for package types, values, and functions or non-obvious lines of code
+- [ ] I am willing to help maintain this change if there are issues with it later

CONTRIBUTING.md

-## Contributing to Caddy
-
-Welcome! Our community focuses on helping others and making Caddy the best it
-can be. We gladly accept contributions and encourage you to get involved!
-
-
-### Join us in the forum
-
-The [Caddy forum](https://forum.caddyserver.com) is the place for all discussion
-that doesn't belong in issues or pull requests. Feel free to participate with us!
-
-If you want to file a bug report or make an improvement to Caddy, however, you
-should submit an issue or pull request.
-
-
-### Bug reports
-
-Please [search this repository](https://github.com/mholt/caddy/search?q=&type=Issues&utf8=%E2%9C%93)
-with a variety of keywords to ensure your bug is not already reported.
-
-If unique, [open an issue](https://github.com/mholt/caddy/issues) and answer the
-questions so we can understand and reproduce the problematic behavior.
-
-The burden is on you to convince us that it is actually a bug in Caddy. This is
-easiest to do when you write clear, concise instructions so we can reproduce
-the behavior (even if it seems obvious). The more detailed and specific you are,
-the faster we will be able to help you. Check out
-[How to Report Bugs Effectively](http://www.chiark.greenend.org.uk/~sgtatham/bugs.html).
-
-Please be kind. :smile: Remember that Caddy comes at no cost to you, and you're
-getting free help. If we helped you, please consider
-[donating](https://caddyserver.com/donate) - it keeps us motivated!
-
-
-### Minor improvements and new tests
-
-Submit [pull requests](https://github.com/mholt/caddy/pulls) at any time for
-minor changes or new tests. Make sure to write tests to assert your change is
-working properly and is thoroughly covered. We'll ask most pull requests to be
-[squashed](http://gitready.com/advanced/2009/02/10/squashing-commits-with-rebase.html),
-especially with small commits.
-
-Your pull request may be thoroughly reviewed. This is because if we accept the
-PR, we also assume responsibility for it, although we would prefer you to
-help maintain your code after it gets merged. 
-
-
-### Proposals, suggestions, ideas, new features
-
-First, please [search](https://github.com/mholt/caddy/search?q=&type=Issues&utf8=%E2%9C%93)
-with a variety of keywords to ensure your suggestion/proposal is new.
-
-If so, you may open either an issue or a pull request for discussion and
-feedback.
-
-The advantage of issues is that you don't have to spend time implementing your
-idea, but you should still describe it thoroughly as if someone reading it would
-implement the whole thing starting from scratch.
-
-The advantage of pull requests is that we can immediately see the impact the
-change will have on the project, what the code will look like, and how to
-improve it. The disadvantage of pull requests is that they are unlikely to get
-accepted without significant changes first, or it may be rejected entirely.
-Don't worry, that won't happen without an open discussion first.
-
-If you are going to spend significant time writing code for a new pull request,
-best to open an issue to "claim" it and get feedback before you invest a lot of
-time. Not all pull requests are merged, and that's okay,
-[Read why.](https://github.com/turbolinks/turbolinks/pull/124#issuecomment-239826060)
-
-Remember: pull requests should always be thoroughly documented both via godoc
-and with at least a rough draft of documentation that might go on the website
-for users to read.
-
-
-### Collaborator status
-
-If your pull request is merged, congratulations! You're technically a
-collaborator. We may also grant you "Collaborator status" which means you can
-push to the repository and merge other pull requests. We hope that you will
-stay involved by reviewing pull requests, submitting more of your own, and
-resolving issues as you are able to. Thanks for making Caddy amazing!
-
-We ask that collaborators will conduct thorough code reviews and be nice to
-new contributors. Before merging a PR, it's best to get the approval of
-at least one or two other collaborators and/or the project owner. We prefer
-squashed commits instead of many little, semantically-unimportant commits. Also,
-CI and other post-commit hooks must pass before being merged except in certain
-unusual circumstances.
-
-Collaborator status may be removed for inactive users from time to time as
-we see fit; this is not an insult, just a basic security precaution in case
-the account becomes inactive or abandoned. Privileges can always be restored
-later.
-
-**Reviewing pull requests:** Please help submit and review pull requests as
-you are able! We would ask that every pull request be reviewed by at least
-one collaborator who did not open the pull request before merging. This will
-help ensure high code quality as new collaborators are added to the project.
-
-Read [CodeReviewComments](https://github.com/golang/go/wiki/CodeReviewComments)
-on the Go wiki for an idea of what we look for in good, clean Go code, and
-check out [what Linus suggests](https://gist.github.com/matthewhudson/1475276)
-for good commit messages.
-
-
-
-### Vulnerabilities
-
-If you've found a vulnerability that is serious, please email me: Matthew dot 
-Holt at Gmail. If it's not a big deal, a pull request will probably be faster.
-
-
-## Thank you
-
-Thanks for your help! Caddy would not be what it is today without your
-contributions.