added a bugtracking system manager, and a manager for bugzilla
changed the model accordingly
git-svn-id: https://svn.cs.york.ac.uk/svn/ossmeter/Software/source@391 1b171192-1bc4-4300-84b6-1b6fde2e8ce3
Authored by: ioannis.korkontzelos@manchester.ac.uk 2013-05-28
Parent(s): [d04020]
Child(ren): [ef9259]