Fix VCS integration save form + GitLab integration

* When both mailing and vcs modules are enabled there is an issues with saving VCS settings, fixed by using a seperate ID for the form
* Added Gitlab specific link settings for integration, can be better, but it works great. the actual commit URL is the github link (http://www.your-tbg-site.com/vcs_integration/report/PROJECTID/github/?passkey=PASSKEY).