fixed issue ACADEMIC-390: Enrolment in groups with 0 vacancies
Bug fix: added missing jsp
Merge pull request #594 from pedrorijo91/issue390

fixed issue ACADEMIC-390: Enrolment in groups with 0 vacancies
Only teachers can add/edit their own credits reductions; Corrected credits reductions functionalities mappings
Bumped version for release of 3.12.4
Merge branch 'release/3.12.4' into develop
Bumped version for development after release.
Bug fix: preventing NPE
Minor change: presenting the default mobile phone, instead of the fixed
phone
Bug fix: the attribute in the request is the object role and not its ID,
retrieving its ID to the link
Minor change: corrected the photo URL
Minor change: added an error message when the nickname update fails
internally