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

models/fixtures/team_repo.yml

@@ -45,3 +45,21 @@
   org_id: 3
   team_id: 1
   repo_id: 32
+
+-
+  id: 9
+  org_id: 3
+  team_id: 7
+  repo_id: 32
+
+-
+  id: 10
+  org_id: 17
+  team_id: 8
+  repo_id: 24
+
+-
+  id: 11
+  org_id: 17
+  team_id: 9
+  repo_id: 24