added checkout action to hid file
moved class definition for BranchesModel::Item as an accessible object
draft implementation of context menu and checkout option (works on local branches)
added class RefItem to later replace the old BranchesModel::Item
adjusted RefsView to use new Git::ReferenceList (not compiling)
adjusted HistoryBuilder and HistoryDiff to GitWrap (not compiling)
updated branches view and model to use the new reference mechanism from GitWrap
mark all references pointing to HEAD in a lighter background color
removed osx focus rect on reference tree
make RefItems editable
added RefItem::setData method (currently only for renaming refs)
added action "rename reference"
added error handling when renaming references
added action "remove reference" without actual functionality yet
update view on error as well
early implementation of action "delete reference" without any safety belts (you have been warned!)
removed classes "RefsView" and "TagsView" and replaced using a single "Branches" model/view concept
minor
added private helper method "askToGoOn"
added safety checks when removing references (needs some proper cleanup, but does the right thing)