git-gui: Include 'war on whitespace' fixes from git.git

Earlier git.git applied a large "war on whitespace" patch that was
created using 'apply --whitespace=strip'.  Unfortunately a few of
git-gui's own files got caught in the mix and were also cleaned up.
That was a6080a0a44.

This patch is needed in git-gui.git to reapply those exact same
changes here, otherwise our version generator script is unable to
obtain our version number from git-describe when we are hosted in
the git.git repository.

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

GIT-VERSION-GEN

@@ -78,5 +78,3 @@ test "$VN" = "$VC" || {
 	echo >&2 "GITGUI_VERSION = $VN"
 	echo "GITGUI_VERSION = $VN" >$GVF
 }
-
-

lib/class.tcl

@@ -151,4 +151,3 @@ auto_mkindex_parser::command constructor {name args} {
 		[format { [list source [file join $dir %s]]} \
 		[file split $scriptFile]] "\n"
 }
-