This PR fixes #7598 by providing a configurable way of signing commits across the Gitea instance. Per repository configurability and import/generation of trusted secure keys is not provided by this PR - from a security PoV that's probably impossible to do properly. Similarly web-signing, that is asking the user to sign something, is not implemented - this could be done at a later stage however.

## Features
- [x] If commit.gpgsign is set in .gitconfig sign commits and files created through repofiles. (merges should already have been signed.)
- [x] Verify commits signed with the default gpg as valid
- [x] Signer, Committer and Author can all be different
    - [x] Allow signer to be arbitrarily different - We still require the key to have an activated email on Gitea. A more complete implementation would be to use a keyserver and mark external-or-unactivated with an "unknown" trust level icon.
- [x] Add a signing-key.gpg endpoint to get the default gpg pub key if available
    - Rather than add a fake web-flow user I've added this as an endpoint on /api/v1/signing-key.gpg
    - [x] Try to match the default key with a user on gitea - this is done at verification time
- [x] Make things configurable?
    - app.ini configuration done
    - [x] when checking commits are signed need to check if they're actually verifiable too
- [x] Add documentation

I have decided that adjusting the docker to create a default gpg key is not the correct thing to do and therefore have not implemented this.

Signed-off-by: Tamal Saha <tamal@appscode.com>

* Add options to git.Clone to make it more capable

* Begin the process of removing the local copy and tidy up

* Remove Wiki LocalCopy Checkouts

* Remove the last LocalRepo helpers

* Remove WithTemporaryFile

* Enable push-hooks for these routes

* Ensure tests cope with hooks

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Remove Repository.LocalCopyPath()

* Move temporary repo to use the standard temporary path

* Fix the tests

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Remove LocalWikiPath

* Fix missing remove

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Use AppURL for Oauth user link (#6894)

* Use AppURL for Oauth user link

Fix #6843

* Update oauth.go

* Update oauth.go

* internal/ssh: ignore env command totally (#6825)

* ssh: ignore env command totally

* Remove commented code 

Needed fix described in issue #6889

* Escape the commit message on issues update and title in telegram hook (#6901)

* update sdk to latest (#6903)

* improve description of branch protection (fix #6886) (#6906)

The branch protection description text were not quite accurate.

* Fix logging documentation (#6904)

* ENABLE_MACARON_REDIRECT should be REDIRECT_MACARON_LOG

* Allow DISABLE_ROUTER_LOG to be set in the [log] section

* [skip ci] Updated translations via Crowdin

* Move sdk structs to modules/structs (#6905)

* move sdk structs to moduels/structs

* fix tests

* fix fmt

* fix swagger

* fix vendor

* Panic don't fatal on create new logger

Fixes #5854

Signed-off-by: Andrew Thornton <art27@cantab.net>

* partial broken

* Update the logging infrastrcture

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Reset the skip levels for Fatal and Error

Signed-off-by: Andrew Thornton <art27@cantab.net>

* broken ncsa

* More log.Error fixes

Signed-off-by: Andrew Thornton <art27@cantab.net>

* Remove nal

* set log-levels to lowercase

* Make console_test test all levels

* switch to lowercased levels

* OK now working

* Fix vetting issues

* Fix lint

* Fix tests

* change default logging to match current gitea

* Improve log testing

Signed-off-by: Andrew Thornton <art27@cantab.net>

* reset error skip levels to 0

* Update documentation and access logger configuration

* Redirect the router log back to gitea if redirect macaron log but also allow setting the log level - i.e. TRACE

* Fix broken level caching

* Refactor the router log

* Add Router logger

* Add colorizing options

* Adjust router colors

* Only create logger if they will be used

* update app.ini.sample

* rename Attribute ColorAttribute

* Change from white to green for function

* Set fatal/error levels

* Restore initial trace logger

* Fix Trace arguments in modules/auth/auth.go

* Properly handle XORMLogger

* Improve admin/config page

* fix fmt

* Add auto-compression of old logs

* Update error log levels

* Remove the unnecessary skip argument from Error, Fatal and Critical

* Add stacktrace support

* Fix tests

* Remove x/sync from vendors?

* Add stderr option to console logger

* Use filepath.ToSlash to protect against Windows in tests

* Remove prefixed underscores from names in colors.go

* Remove not implemented database logger

This was removed from Gogs on 4 Mar 2016 but left in the configuration
since then.

* Ensure that log paths are relative to ROOT_PATH

* use path.Join

* rename jsonConfig to logConfig

* Rename "config" to "jsonConfig" to make it clearer

* Requested changes

* Requested changes: XormLogger

* Try to color the windows terminal

If successful default to colorizing the console logs

* fixup

* Colorize initially too

* update vendor

* Colorize logs on default and remove if this is not a colorizing logger

* Fix documentation

* fix test

* Use go-isatty to detect if on windows we are on msys or cygwin

* Fix spelling mistake

* Add missing vendors

* More changes

* Rationalise the ANSI writer protection

* Adjust colors on advice from @0x5c

* Make Flags a comma separated list

* Move to use the windows constant for ENABLE_VIRTUAL_TERMINAL_PROCESSING

* Ensure matching is done on the non-colored message - to simpify EXPRESSION

* split setting.go to multiple files

* fix lint