Changing name to Gitlab Mattermost Support Forum

README.md

-Gitlab Mattermost
------------------
+Gitlab Mattermost Support Forum
+-------------------------------
 Gitlab Mattermost is a team communication service for sharing messages and
 files across PCs and phones, with archiving and instant search.
@@ -17,4 +17,4 @@ https://gitlab.com/gitlab-org/gitlab-mattermost/issues)**.
 Thank you kindly for trying out Gitlab Mattermost. 
-We look forward to your feedback and questions. 
\ No newline at end of file
+We look forward to your feedback and questions.
\ No newline at end of file