Restrict permission check on repositories and fix some problems (#5314)

* fix units permission problems

* fix some bugs and merge LoadUnits to repoAssignment

* refactor permission struct and add some copyright heads

* remove unused codes

* fix routes units check

* improve permission check

* add unit tests for permission

* fix typo

* fix tests

* fix some routes

* fix api permission check

* improve permission check

* fix some permission check

* fix tests

* fix tests

* improve some permission check

* fix some permission check

* refactor AccessLevel

* fix bug

* fix tests

* fix tests

* fix tests

* fix AccessLevel

* rename CanAccess

* fix tests

* fix comment

* fix bug

* add missing unit for test repos

* fix bug

* rename some functions

* fix routes check

templates/repo/settings/webhook/history.tmpl

@@ -1,7 +1,7 @@
 {{if .PageIsSettingsHooksEdit}}
 	<h4 class="ui top attached header">
 		{{.i18n.Tr "repo.settings.recent_deliveries"}}
-		{{if .IsRepositoryAdmin}}
+		{{if .Permission.IsAdmin}}
 			<div class="ui right">
 				<button class="ui teal tiny button poping up" id="test-delivery" data-content=
 				"{{.i18n.Tr "repo.settings.webhook.test_delivery_desc"}}" data-variation="inverted tiny" data-link="{{.Link}}/test" data-redirect="{{.Link}}">{{.i18n.Tr "repo.settings.webhook.test_delivery"}}</button>