improve output

[yaniksoeltzer]

Improve the output, so that any user without further usage understands it.
For example the current output:

untracked branches:
     /root
     /root/docker_builds/reverse_proxy
6 git repositories found with 2 warnings.

is not intuitive.
For example:

inspected 6 git repositories and found 2 warnings:
branches that are not tracked by a remote branch:
     /root @master
     /root/docker_builds/reverse_proxy @master

[yaniksoeltzer]

maybe add a additional text for each report class, that explains what the issue is and how to resolve it.