Create TSOutgoingMessage with info on group change

TSOutgoingMessage is created with details about the group changes so that we see more than just “Group Updated.”

* Customizes message for new group creation
  Replaces GROUP_UPDATED with GROUP_CREATED for a brand new group. Localized for English only.

* Updates to use fixed SignalServiceKit branch

// FREEBIE

Podfile.lock

@@ -134,7 +134,7 @@ EXTERNAL SOURCES:
 
 CHECKOUT OPTIONS:
   SignalServiceKit:
-    :commit: 91fcd01632a81f2aa67d2d94b97c68d519e6881a
+    :commit: d4c55d69404c99927da716c443997415ad7bc6ba
     :git: https://github.com/WhisperSystems/SignalServiceKit.git
   SocketRocket:
     :commit: 41b57bb2fc292a814f758441a05243eb38457027

Signal/src/view controllers/MessagesViewController.m

@@ -2027,14 +2027,19 @@ typedef enum : NSUInteger {
     __block TSOutgoingMessage *message;
 
     [self.editingDatabaseConnection readWriteWithBlock:^(YapDatabaseReadWriteTransaction *transaction) {
-      groupThread            = [TSGroupThread getOrCreateThreadWithGroupModel:newGroupModel transaction:transaction];
-      groupThread.groupModel = newGroupModel;
-      [groupThread saveWithTransaction:transaction];
-      message = [[TSOutgoingMessage alloc] initWithTimestamp:[NSDate ows_millisecondTimeStamp]
-                                                    inThread:groupThread
-                                                 messageBody:@""
-                                               attachmentIds:[NSMutableArray new]];
-      message.groupMetaMessage = TSGroupMessageUpdate;
+        groupThread = [TSGroupThread getOrCreateThreadWithGroupModel:newGroupModel transaction:transaction];
+
+        NSString *updateGroupInfo =
+            [groupThread.groupModel getInfoStringAboutUpdateTo:newGroupModel contactsManager:self.contactsManager];
+
+        groupThread.groupModel = newGroupModel;
+        [groupThread saveWithTransaction:transaction];
+        message = [[TSOutgoingMessage alloc] initWithTimestamp:[NSDate ows_millisecondTimeStamp]
+                                                      inThread:groupThread
+                                                   messageBody:@""
+                                                 attachmentIds:[NSMutableArray new]];
+        message.groupMetaMessage = TSGroupMessageUpdate;
+        message.customMessage = updateGroupInfo;
     }];
 
     if (newGroupModel.groupImage != nil) {

Signal/src/view controllers/NewGroupViewController.m

@@ -138,6 +138,7 @@ static NSString *const kUnwindToMessagesViewSegue = @"UnwindToMessagesViewSegue"
                                                             messageBody:@""
                                                           attachmentIds:[NSMutableArray new]];
                        message.groupMetaMessage = TSGroupMessageNew;
+                       message.customMessage = NSLocalizedString(@"GROUP_CREATED", nil);
                        if (model.groupImage != nil) {
                            [[TSMessagesManager sharedManager] sendAttachment:UIImagePNGRepresentation(model.groupImage)
                                contentType:OWSMimeTypeImagePng