added google sign-in functionality to the client, with minor model modifications

web/react/utils/async_client.jsx

@@ -390,15 +390,15 @@ module.exports.getPosts = function(force, id, maxPosts) {
     }
 }
 
-function getMe() {
-    if (isCallInProgress('getMe')) {
+function getMeSynchronous() {
+    if (isCallInProgress('getMeSynchronous')) {
         return;
     }
 
-    callTracker.getMe = utils.getTimestamp();
-    client.getMe(
+    callTracker.getMeSynchronous = utils.getTimestamp();
+    client.getMeSynchronous(
         function(data, textStatus, xhr) {
-            callTracker.getMe = 0;
+            callTracker.getMeSynchronous = 0;
 
             if (xhr.status === 304 || !data) return;
 
@@ -409,11 +409,11 @@ function getMe() {
         },
         function(err) {
             callTracker.getMe = 0;
-            dispatchError(err, 'getMe');
+            dispatchError(err, 'getMeSynchronous');
         }
     );
 }
-module.exports.getMe = getMe;
+module.exports.getMeSynchronous = getMeSynchronous;
 
 module.exports.getStatuses = function() {
     if (isCallInProgress('getStatuses')) return;

web/react/utils/client.jsx

@@ -279,24 +279,33 @@ module.exports.getAudits = function(userId, success, error) {
     });
 };
 
-module.exports.getMe = function(success, error) {
+module.exports.getMeSynchronous = function(success, error) {
+    var currentUser = null;
 
     $.ajax({
+        async: false,
         url: "/api/v1/users/me",
         dataType: 'json',
         contentType: 'application/json',
         type: 'GET',
-        success: success,
+        success: function gotUser(data, textStatus, xhr) {
+            currentUser = data;
+            if (success) {
+                success(data, textStatus, xhr);
+            }
+        },
         error: function(xhr, status, err) {
             var ieChecker = window.navigator.userAgent; // This and the condition below is used to check specifically for browsers IE10 & 11 to suppress a 200 'OK' error from appearing on login
             if (xhr.status != 200 || !(ieChecker.indexOf("Trident/7.0") > 0 || ieChecker.indexOf("Trident/6.0") > 0)) {
                 if (error) {
-                    e = handleError("getMe", xhr, status, err);
+                    e = handleError('getMeSynchronous', xhr, status, err);
                     error(e);
                 };
             };
         }
     });
+
+    return currentUser;
 };
 
 module.exports.inviteMembers = function(data, success, error) {

web/react/utils/constants.jsx

@@ -58,6 +58,8 @@ module.exports = {
   THUMBNAIL_HEIGHT: 100,
   DEFAULT_CHANNEL: 'town-square',
   OFFTOPIC_CHANNEL: 'off-topic',
+  GITLAB_SERVICE: 'gitlab',
+  GOOGLE_SERVICE: 'google',
   POST_CHUNK_SIZE: 60,
   MAX_POST_CHUNKS: 3,
   RESERVED_TEAM_NAMES: [