* Add a markdown stripper for mentions and xrefs

* Improve comments

* Small code simplification

* Move reference code to modules/references

* Fix typo

* Make MarkdownStripper return [][]byte

* Implement preliminary keywords parsing

* Add FIXME comment

* Fix comment

* make fmt

* Fix permissions check

* Fix text assumptions

* Fix imports

* Fix lint, fmt

* Fix unused import

* Add missing export comment

* Bypass revive on implemented interface

* Move mdstripper into its own package

* Support alphanumeric patterns

* Refactor FindAllMentions

* Move mentions test to references

* Parse mentions from reference package

* Refactor code to implement renderizable references

* Fix typo

* Move patterns and tests to the references package

* Fix nil reference

* Preliminary rendering attempt of closing keywords

* Normalize names, comments, general tidy-up

* Add CSS style for action keywords

* Fix permission for admin and owner

* Fix golangci-lint

* Fix golangci-lint

* Draft for ResolveMentionsByVisibility()

* Correct typo

* Resolve teams instead of orgs for mentions

* Create test for ResolveMentionsByVisibility

* Fix check for individual users and doer

* Test and fix team mentions

* Run all mentions through visibility filter

* Fix error check

* Simplify code, fix doer included in teams

* Simplify team id list build

* 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