LUN-1563: Make sure the auto-generated site permission does not exceed the max length of the DB field
LUN-1563: delete unused import
LUN-1563: simplified the logic of group name generation
LUN-1563: re-added the group_name regex pattern back as a member of the Role class, because it is used in tests
Merge pull request #27 from pbs/LUN-1563

Lun 1563