Cleanup changelog after some hotfix releases.

The backporting of some hotfix features, weren't executed all that cleanly.
Therefore some manuel cherry-picking adjustments are needed.
MainDossierTest rework: Manually cherry pick of 4d1510fcea4ec270d26c6d4ab9923d294fee92ff.
Added reviewer role on admin groups.
This role ensures that admins can see the menu bar.
Merge pull request #273 from 4teamwork/lk_reviewer_on_admin

Added reviewer role on admin groups.
Merge pull request #313 from 4teamwork/pg_3.1.x_backport_cleanup

Pg 3.1.x backport cleanup
Dossierdetails: Fixed label for the `end` attribute.
Merge pull request #317 from 4teamwork/pg_dossierdetails_label_fix

Dossierdetails: Fixed label for the `end` attribute.
Added download copy in tooltip.