Removed Bolonha 1st cycle degrees from incoming mobility programmes options.
Added support for modifying a student's mobility programme.
Modified criation of incoming mobility vacancies to allow the creation of multiple vacancies at the same time
Added support for modifying a student's chosen degree.
Closes #522
Merge pull request #524 from AfonsoFGarcia/externalCandidacies

Removed Bolonha 1st cycle degrees from incoming mobility programmes options.
Added support for modifying a student's mobility programme.
Modified criation of incoming mobility vacancies to allow the creation of multiple vacancies at the same time
Added support for modifying a student's chosen degree.
Closes #522