Add support for multiple repositories: fixes

Feature start now lists only stories with the relevant PT label on.
Finished feature 60403452/include-exclude-tags.
Add support for 'no review' PT label

Developers can now add 'no review' label to a PT story to let GF know that it
should not expect any review for that story. This allows greater granularity
than simply using -R, which simply skips all code review checks.
Finished feature 57488030/no-review-label.
multiple repos: Implement include/exclude

From now on it is not necessary to use repo- prefix from the repository labels.
Instead of it you define a label filter for each repository. The filter either
includes a single PT label, or excludes any number of PT labels.

This is again being asked during git flow init. If no include label is defined,
the exclude labels question is asked and it's expecting a comman-separated list
of labels. If both questions are answered with an empty reply, gitflow behaves
exactly as it used to.
Finished feature 60403452/include-exclude-tags.
Some minor fixes, code cleanup
Finished feature 60403452/include-exclude-tags.
Bump version to 1.2.0
Fix a wrong continue in a lopp
Finished release 1.2.0 (merge into develop)