Compatible with GitLab 6 and GitLab CI 3

* Updated all relevant files to support new versions
  - GitLab 6.0.1
  - GitLab Shell 1.7.1
  - GitLab CI 3.1.0
* Strictly seperated GitLab and GitLab CI
  Now you can install GitLab CI without installing GitLab and GitLab Shell
* Seperated Git and Ruby into own recipes
  Now you can decide if you want to install Git/Ruby from package or from source
* Changed Webserver to be configurable (like database)
* Removed writing of bashrc and placed a script into profile.d instead