Merge git://repo.or.cz/git-gui into pt/git-gui
* git://repo.or.cz/git-gui:
git-gui: fix size and position of window panes on startup
git-gui: mc cannot be used before msgcat has been loaded
git-gui: use textconv filter for diff and blame
git-gui: Avoid using the <<Copy>> binding as a menu accelerator on win32
git-gui: fix shortcut creation on cygwin
git-gui: fix PATH environment for mingw development environment
git-gui: fix usage of _gitworktree when creating shortcut for windows
git-gui: fix "Explore Working Copy" for Windows again
git-gui: fix usage of themed widgets variable
git-gui: Handle failure of core.worktree to identify the working directory.
git-gui: check whether systems nice command works or disable it