BCS 746-000808

This is needed for cases where the remote URL contains a part of the project namespace (e.g. "ssh://git@gitlab.com/garz-fricke/yocto") and the project name contains another part of it (e.g. "layers/meta-guf-machine"). There is no GitLab API call which will find a project given this information.
Thus we are adding a possibility to parse the namespace from the remote and prepend it to the project name in order to return it including its complete namespace (e.g. "garz-fricke/yocto/layers/meta-guf-machine").

* Add retrigger_mr_pipeline_py script
* Move get_merge_request() function to separate file and make it return all
  available pipelines instead of just one
* Add helper script for parsing projects from manifest file