gitk: On OSX, bring the gitk window to front
gitk: On OSX, bring the gitk window to front

On OSX, Tcl/Tk application windows are created behind all
the applications down the stack of windows.  This is very
annoying, because once a gitk window appears, it's the
downmost window and switching to it is pain.

The patch is: if we are on OSX, use osascript to
bring the current Wish process window to front.

Signed-off-by: Tair Sabirgaliev <a4d392d548c8fc990237f8951eca9167ead9fbd8@gmail.com>
Thanks-to: Stefan Haller <da2ea5bee82302925a2874f529684e980c179d70@haller-berlin.de>
Signed-off-by: Paul Mackerras <19a0ba370c443ba08d20b5061586430ab449ee8c@samba.org>

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git