[ticket/14168] Refactor attachment management functions into classes * marc1706/ticket/14168: (36 commits) [ticket/14168] Correctly state return type of upload and upload_attachment [ticket/14168] Use attachment manager instead of separate classes [ticket/14168] Fix docblock in manager [ticket/14168] Add more test cases for attachment manager [ticket/14168] Add new test method and more tests [ticket/14168] Fix tabs in manager and add test file [ticket/14168] Fix tests after rebase [ticket/14168] Add attachment manager service [ticket/14168] Use correct docblock [ticket/14168] Add services_attachment.yml to services.yml [ticket/14168] Minor coding style fixes [ticket/14168] Move attachment service definitions to services_attachment [ticket/14168] Improve code coverage in upload class [ticket/14168] Move image check and don't use trigger_error() [ticket/14168] Add tests for init_error() during upload [ticket/14168] Add basic test file for attachments upload [ticket/14168] Fix CS issue [ticket/14168] No longer use deprecated functions in core files [ticket/14168] Move phpbb_unlink() into attachment delete class [ticket/14168] Reset sequence before tests in delete tests ...