* Mulitple Gitea Doctor improvements (#10943)
Backport #10943
* Add `gitea doctor --list` flag to list the checks that will be run, including those by default
* Add `gitea doctor --run` to run specific checks
* Add `gitea doctor --all` to run all checks
* Add db version checker
* Add non-default recalculate merge bases check/fixer to doctor
* Add hook checker (Fix#9878) and ensure hooks are executable (Fix#6319)
* Fix authorized_keys checker - slight change of functionality here because parsing the command is fragile and we should just check if the authorized_keys file is essentially the same as what gitea would produce. (This is still not perfect as order matters - we should probably just md5sum the two files.)
* Add SCRIPT_TYPE check (Fix#10977)
* Add `gitea doctor --fix` to attempt to fix what is possible to easily fix
* Add `gitea doctor --log-file` to set the log-file, be it a file, stdout or to switch off completely. (Fixes previously undetected bug with certain xorm logging configurations - see @6543 comment.)
Signed-off-by: Andrew Thornton <art27@cantab.net>
* Switch to io.Writer instead of io.StringWriter
Signed-off-by: Andrew Thornton <art27@cantab.net>
* move all mail related codes from models to modules/mailer
* fix lint
* use DBContext instead Engine
* use WithContext not WithEngine
* Use DBContext instead of Engine
* don't use defer when sess.Close()
* move DBContext to context.go and add some methods
* move mailer from modules/ to services
* fix lint
* fix tests
* fix fmt
* add gitea copyright
* fix tests
* don't expose db functions
* make code clear
* add DefaultDBContext
* fix build
* fix bug
