Added boolean flag to force a branch deletion
Added test for forced branch deletion in Repository
Added test for forced branch deletion in BranchCommand
Merge pull request #64 from adamlacoste/force-delete

Force delete
removed execution in command test
removed @deprecated annotation as GitElephant officially supports git >= 1.8
Added several new features to the Merge command, including the ability to specify a commit message (applicable only when a merge commit is created in a 3-way merge) and to force the merge mode into fast forward or 3-way only.  Also included unit testing for these features.