Gracefully handle SMTP user input errors (e.g. incorrect email addresses) to prevent Sidekiq retries

### What does this MR do?

This MR gracefully handles SMTP input errors (e.g. incorrect or invalid e-mail addresses) to prevent these types of exceptions from causing Sidekiq to retry the task. If these specific exceptions occur, they will be logged, and the e-mail will be dropped from the queue.

### Why was this MR needed?

If you include an author that has a misspelled e-mail address, Sidekiq will keep sending e-mail to all the recipients even if they have already received the e-mail. The only way to recover is to clear the Sidekiq queue.

Note that other exceptions can still be thrown (e.g. `IOError`, `Net::SMTPAuthenticationError`, `Net::SMTPServerBusy`, `Net::SMTPUnknownError`, and `TimeoutError`). If the worker encounters these, Sidekiq should retry the task.

### What are the relevant issue numbers?

Closes https://github.com/gitlabhq/gitlabhq/issues/9560

See merge request !1163

Upgrade browser gem to 1.0.0 to avoid warning in IE11 compatibilty mode

GitLab currently displays the "outdated browser" message if users run Internet Explorer 11 in Compatibility Mode. @fnando [updated the browser gem](https://github.com/fnando/browser/pull/168) to use IE's Trident version to determine the "true" version of IE11.

Closes #2271

See merge request !1188

Ignore empty incoming messages (Reply by email)

We should also update mail_room when https://github.com/tpitale/mail_room/pull/35 goes in, but that can wait a bit.

See merge request !1190

Move changelog entry to 7.14.1

[ci skip]

See merge request !1192

[ci skip]

Move full_host fix changelog entry to 7.14.1

[ci skip]

See merge request !1191

[ci skip]

Only include base URL in OmniAuth full_host parameter

Closes #2335

See merge request !1187

Fix Error 500 in API when accessing a group that has an avatar

Closes #2340

See merge request !1189

Closes #2340

Ability to search milestones

https://dev.gitlab.org/gitlab/gitlabhq/issues/2473

See merge request !1158

Closes #2271

Remove user OAuth tokens stored in database for Bitbucket, GitHub, and GitLab and request them each session

Remove user OAuth tokens stored in database for Bitbucket, GitHub, and GitLab
and request them each session. Pass these tokens to the project import data.

This prevents the need to encrypt these tokens and clear them in case they
expire or get revoked.

For example, if you deleted and re-created OAuth2 keys for Bitbucket, you would get
an Error 500 with no way to recover:

```
Started GET "/import/bitbucket/status" for x.x.x.x at 2015-08-07 05:24:10 +0000
Processing by Import::BitbucketController#status as HTML
Completed 500 Internal Server Error in 607ms (ActiveRecord: 2.3ms)

NameError (uninitialized constant Import::BitbucketController::Unauthorized):
  app/controllers/import/bitbucket_controller.rb:77:in `rescue in go_to_bitbucket_for_permissions'
  app/controllers/import/bitbucket_controller.rb:74:in `go_to_bitbucket_for_permissions'
  app/controllers/import/bitbucket_controller.rb:86:in `bitbucket_unauthorized'
```
Closes #1871

See merge request !1112

Closes #2335

and request them each session. Pass these tokens to the project import data.

This prevents the need to encrypt these tokens and clear them in case they
expire or get revoked.

For example, if you deleted and re-created OAuth2 keys for Bitbucket, you would get
an Error 500 with no way to recover:

```
Started GET "/import/bitbucket/status" for x.x.x.x at 2015-08-07 05:24:10 +0000
Processing by Import::BitbucketController#status as HTML
Completed 500 Internal Server Error in 607ms (ActiveRecord: 2.3ms)

NameError (uninitialized constant Import::BitbucketController::Unauthorized):
  app/controllers/import/bitbucket_controller.rb:77:in `rescue in go_to_bitbucket_for_permissions'
  app/controllers/import/bitbucket_controller.rb:74:in `go_to_bitbucket_for_permissions'
  app/controllers/import/bitbucket_controller.rb:86:in `bitbucket_unauthorized'
```

Closes #1871

"Fixes #xxxx" now shows up in the issue log for non-default branches. #2190

I don't understand why the commits containing "closing references" (like `closes #xxxx`) were not mentioned in the corresponding issues **when pushed to a non-default branch**.

So I tried to discover how it works -- hence learning Ruby! I don't expect that MR to pass, this is my very first attempt of contribution.

**Update:** my modifications are now done. To sum up:
- when a commit with a reference `fixes #xxxx` is pushed to a non-default branch, a cross-reference to that issue will be created;
- when that same commit is pushed to a default branch, no cross-reference will be created because a message `This commit closes issue` will be emitted.
- I also refined some of the existing tests and added 2 tests on the new behavior on non-default branches.

See merge request !1150

I also revamped the tests on "closing reference commits" (= "Fixes #xxxx" for example).
Now, there are two different contexts:
- when the commits with "closing reference" are pushed to the default branch,
- when the commits with "closing reference" are pushed to a non-default branch.

Closes gitlab-org/gitlab-ce#2190.

Reply by email

Fixes #1360.

It's far from done, but _it works_.

See merge request !1173

Fix bug preventing invite by e-mail

This was broken in 70f52918 as a result of introducing the ability to filter by current user.

Closes #2320

See merge request !1181

This was broken in 70f52918 as a result of introducing the ability to filter by current user.

Closes #2320

Remove trailing HTML entities from non-Rinku autolinks as well.

Addresses internal https://dev.gitlab.org/gitlab/gitlabhq/issues/2550

See merge request !1179

Check permissions on target project in merge request create service.

See merge request !1183

Fix bug where non-project members of the target project could set labels on new merge requests.

Fixes #2292.

See merge request !1180

Do not delete the SQL dump too early

The change in baa15792 broke backup
restore fucnctionality. This would not lead to data loss, but it
prevented the restore script from working. This bug exists only in
7.14.0 release candidate versions, not in 7.13.

Reported in https://github.com/gitlabhq/gitlabhq/issues/9571 .

See merge request !1182

Fixed JS issue with diff image loading

Fixes #1323

Whilst I couldn't reproduce the error locally, I did manage to get the same JS error message that was in the live env.

See merge request !463

Only show recent push event if the branch still exists or a recent merge request has not been created

Closes #2277

See merge request !1167

Case-insensitive search for comments
Signed-off-by: Dmitriy Zaporozhets <dmitriy.zaporozhets@gmail.com>

See merge request !1174

The change in baa15792 broke backup
restore fucnctionality. This would not lead to data loss, but it
prevented the restore script from working. This bug exists only in
7.14.0 release candidate versions, not in 7.13.

Reported in https://github.com/gitlabhq/gitlabhq/issues/9571 .