PLT-3143 Added serverside code for custom Emoji (#3311)

* Added model objects for emoji

* Added database tables for emoji

* Added settings for custom emoji

* Added serverside APIs and unit tests for custom emoji

* Added additional validation to catch duplicate emoji names earlier on

* Added additional validation to prevent users from adding emoji as another user

api/api.go

@@ -46,6 +46,8 @@ type Routes struct {
 	License *mux.Router // 'api/v3/license'
 
 	Public *mux.Router // 'api/v3/public'
+
+	Emoji *mux.Router // 'api/v3/emoji'
 }
 
 var BaseRoutes *Routes
@@ -72,6 +74,7 @@ func InitApi() {
 	BaseRoutes.Preferences = BaseRoutes.ApiRoot.PathPrefix("/preferences").Subrouter()
 	BaseRoutes.License = BaseRoutes.ApiRoot.PathPrefix("/license").Subrouter()
 	BaseRoutes.Public = BaseRoutes.ApiRoot.PathPrefix("/public").Subrouter()
+	BaseRoutes.Emoji = BaseRoutes.ApiRoot.PathPrefix("/emoji").Subrouter()
 
 	InitUser()
 	InitTeam()
@@ -86,6 +89,7 @@ func InitApi() {
 	InitWebhook()
 	InitPreference()
 	InitLicense()
+	InitEmoji()
 
 	// 404 on any api route before web.go has a chance to serve it
 	Srv.Router.Handle("/api/{anything:.*}", http.HandlerFunc(Handle404))