[API] Add Reactions (#9220)

* reject reactions wich ar not allowed

* dont duble check CreateReaction now throw ErrForbiddenIssueReaction

* add /repos/{owner}/{repo}/issues/comments/{id}/reactions endpoint

* add Find Functions

* fix some swagger stuff + add issue reaction endpoints + GET ReactionList now use FindReactions...

* explicite Issue Only Reaction for FindReactionsOptions with "-1" commentID

* load issue; load user ...

* return error again

* swagger def canged after LINT

* check if user has ben loaded

* add Tests

* better way of comparing results

* add suggestion

* use different issue for test
(dont interfear with integration test)

* test dont compare Location on timeCompare

* TEST: add forbidden dubble add

* add comments in code to explain

* add settings.UI.ReactionsMap
so if !setting.UI.ReactionsMap[opts.Type] works

models/fixtures/reaction.yml

@@ -1 +1,39 @@
-[] # empty
+-
+  id: 1 #issue reaction
+  type: zzz # not allowed reaction (added before allowed reaction list has changed)
+  issue_id: 1
+  comment_id: 0
+  user_id: 2
+  created_unix: 1573248001
+
+-
+  id: 2 #issue reaction
+  type: zzz # not allowed reaction (added before allowed reaction list has changed)
+  issue_id: 1
+  comment_id: 0
+  user_id: 1
+  created_unix: 1573248002
+
+-
+  id: 3 #issue reaction
+  type: eyes # allowed reaction
+  issue_id: 1
+  comment_id: 0
+  user_id: 2
+  created_unix: 1573248003
+
+-
+  id: 4 #comment reaction
+  type: laugh # allowed reaction
+  issue_id: 1
+  comment_id: 2
+  user_id: 2
+  created_unix: 1573248004
+
+-
+  id: 5 #comment reaction
+  type: laugh # allowed reaction
+  issue_id: 1
+  comment_id: 2
+  user_id: 1
+  created_unix: 1573248005