git-mv: fully detect 'directory moved into itself'
git-mv: fully detect 'directory moved into itself'

This gives a better error message when trying to move a directory
into some subdirectory of itself; ie. no real bug fix: renaming
already failed before, but with a strange "invalid argument".

Signed-off-by: Josef Weidendorfer <cd09c6f9ce317d005f2d2d124e6e1764b163fdc4@gmx.de>
Signed-off-by: Junio C Hamano <dc50d1021234060e53ec42a77d526afa2fe07479@cox.net>

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