Merge git://repo.or.cz/git-gui

* git://repo.or.cz/git-gui: git-gui: "Stage Line": Treat independent changes in adjacent lines better git-gui: Fix "Stage/Unstage Line" with one line of context. git-gui: Correct 'Visualize Branches' on Mac OS X to start gitk git-gui: Look for gitk in $PATH, not $LIBEXEC/git-core Add a menu item to invoke full copy detection in blame. Kill the blame back-end on window close. Add options to control the search for copies in blame. Fix pre-commit hooks under MinGW/MSYS