proxy: recognize client's cancellation

Context: add Push action

lint fixes

fix issue #1589
Signed-off-by: Tw <tw19881113@gmail.com>

Signed-off-by: Tw <tw19881113@gmail.com>

* update to match same paths as systemd

* update to match new launchd plist

* generated from scratch with LaunchControl, flawless

Had some issues with the previous go and found LaunchControl which made it easy to generate a perfectly correct launchd conf

* Update README.md

* Strip brackets in IsInternal if no port, allow loopback for CA URLs

* Fix a mistake

* Improve the trim

* Fix comment

* gzip: add benchmark
Signed-off-by: Tw <tw19881113@gmail.com>

* gzip: pool gzip.Writer to reduce allocation
Signed-off-by: Tw <tw19881113@gmail.com>

Also disable some tests on context.Hostname because they're not portable

proxy: take original URL path into account when remove prefix ("without")

fix issue #1604
Signed-off-by: Tw <tw19881113@gmail.com>

httpserver: Don't close stdout or stderr when closing logs (fix #1471)

* Disable warning for insecure CA if located on private network.
 * Add IsPrivateNetwork function
 * Add tests
Signed-off-by: Jonas Östanbäck <jonas.ostanback@gmail.com>

* Add more testcases
Signed-off-by: Jonas Östanbäck <jonas.ostanback@gmail.com>

* Rename IsPrivateNetwork -> IsInternal
Signed-off-by: Jonas Östanbäck <jonas.ostanback@gmail.com>

templates: Add Hostname template action

This adds the ability to display the remote hostname
of the visitors IP with template actions.

template: add test for custom function

Signed-off-by: Tw <tw19881113@gmail.com>

template: support custom functions

Signed-off-by: Tw <tw19881113@gmail.com>

proxy: use untouched URL for concatenating

Maps are NOT ordered at runtime but I still want the cipher suites
listed in order of preference in the source file for convenience.

Original feature request in forum:
https://forum.caddyserver.com/t/caddy-with-specific-hosts-but-on-demand-tls/1704?u=matt

Before, Caddy obtained certificates for every name it could at startup.
And it would only obtain certificates during the handshake for sites
defined with a hostname that didn't qualify at startup (like
"*.example.com" or ":443"). This made sense for most situations, and
helped ensure that certificates were obtained as early and reliably as
possible.

With this change, Caddy will NOT obtain certificates for hostnames it
knows at startup (even if they qualify) if OnDemand is enabled.

But I think this change generalizes well, because a user who specifies
max_certs is deliberately turning on On-Demand TLS, fully aware of
the consequences. It seems dubious to ignore that config when the user
deliberately put it there. We'll see how this goes.

Signed-off-by: Tw <tw19881113@gmail.com>

* caddyhttp: Allow to alternate Index

* Move Index directive

* Fix misspelling outside this PR

log: only allow new roller related options in a block

proxy: Fix #1574; health check now respects hostname when upstream Host header is configured (#1577)

* Implement adding Host header to health check

* Fix type problems

* Fix duplicate function, Replace args

* Add debugging

* Add debugging

* Add debugging

* Add debugging

* Attempt to set req.Host instead of the header

* Clean up debugging

* Fix missing newline

* Fix spelling

* Add test, refactoring

* Fix with gofmt

* Add error check on NewRequest