Make git-cvsimport remove ['s from tags, as bad_ref_char doesn't allow them.

Signed-off-by: Paul Oliver <puzza007@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-cvsimport.perl

@@ -780,6 +780,7 @@ sub commit {
 		$xtag =~ s/\s+\*\*.*$//; # Remove stuff like ** INVALID ** and ** FUNKY **
 		$xtag =~ tr/_/\./ if ( $opt_u );
 		$xtag =~ s/[\/]/$opt_s/g;
+		$xtag =~ s/\[//g;
 
 		system('git-tag', '-f', $xtag, $cid) == 0
 			or die "Cannot create tag $xtag: $!\n";