PLT-1378 Initial version of emoji reactions (#4520)

* Refactored emoji.json to support multiple aliases and emoji categories

* Added custom category to emoji.jsx and stabilized all fields

* Removed conflicting aliases for :mattermost: and :ca:

* fixup after store changes

* Added emoji reactions

* Removed reactions for an emoji when that emoji is deleted

* Fixed incorrect test case

* Renamed ReactionList to ReactionListView

* Fixed 👍 and 👎 not showing up as possible reactions

* Removed text emoticons from emoji reaction autocomplete

* Changed emoji reactions to be sorted by the order that they were first created

* Set a maximum number of listeners for the ReactionStore

* Removed unused code from Textbox component

* Fixed reaction permissions

* Changed error code when trying to modify reactions for another user

* Fixed merge conflicts

* Properly applied theme colours to reactions

* Fixed ESLint and gofmt errors

* Fixed ReactionListContainer to properly update when its post prop changes

* Removed unnecessary escape characters from reaction regexes

* Shared reaction message pattern between CreatePost and CreateComment

* Removed an unnecessary select query when saving a reaction

* Changed reactions route to be under /reactions

* Fixed copyright dates on newly added files

* Removed debug code that prevented all unit tests from being ran

* Cleaned up unnecessary code for reactions

* Renamed ReactionStore.List to ReactionStore.GetForPost

webapp/client/client.jsx

@@ -2005,11 +2005,11 @@ export default class Client {
 
     removeCertificateFile(filename, success, error) {
         request.
-        post(`${this.getAdminRoute()}/remove_certificate`).
-        set(this.defaultHeaders).
-        accept('application/json').
-        send({filename}).
-        end(this.handleResponse.bind(this, 'removeCertificateFile', success, error));
+            post(`${this.getAdminRoute()}/remove_certificate`).
+            set(this.defaultHeaders).
+            accept('application/json').
+            send({filename}).
+            end(this.handleResponse.bind(this, 'removeCertificateFile', success, error));
     }
 
     samlCertificateStatus(success, error) {
@@ -2030,6 +2030,33 @@ export default class Client {
         });
     }
 
+    saveReaction(channelId, reaction, success, error) {
+        request.
+            post(`${this.getChannelNeededRoute(channelId)}/posts/${reaction.post_id}/reactions/save`).
+            set(this.defaultHeaders).
+            accept('application/json').
+            send(reaction).
+            end(this.handleResponse.bind(this, 'saveReaction', success, error));
+    }
+
+    deleteReaction(channelId, reaction, success, error) {
+        request.
+            post(`${this.getChannelNeededRoute(channelId)}/posts/${reaction.post_id}/reactions/delete`).
+            set(this.defaultHeaders).
+            accept('application/json').
+            send(reaction).
+            end(this.handleResponse.bind(this, 'deleteReaction', success, error));
+    }
+
+    listReactions(channelId, postId, success, error) {
+        request.
+            get(`${this.getChannelNeededRoute(channelId)}/posts/${postId}/reactions`).
+            set(this.defaultHeaders).
+            type('application/json').
+            accept('application/json').
+            end(this.handleResponse.bind(this, 'listReactions', success, error));
+    }
+
     webrtcToken(success, error) {
         request.post(`${this.getWebrtcRoute()}/token`).
         set(this.defaultHeaders).