git-gui: Change summary of git-gui.
git-gui: Change summary of git-gui.

Since git-gui does more than create commits, it is unfair to call
it "a commit creation tool".  Instead lets just call it a graphical
user interface.

Signed-off-by: Shawn O. Pearce <f01032651c12a22b2103346ba96b3b6b231f9d3c@spearce.org>

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