git-gui: learn more type change states

Support the following states with type change in git-gui: AT, MT, TD, TM

Signed-off-by: Bert Wesarg <bert.wesarg@googlemail.com>
Signed-off-by: Pat Thoyts <patthoyts@users.sourceforge.net>
diff --git a/lib/commit.tcl b/lib/commit.tcl
index 83b3d9d..5ce4687 100644
--- a/lib/commit.tcl
+++ b/lib/commit.tcl
@@ -166,7 +166,7 @@
 		_? {continue}
 		A? -
 		D? -
-		T_ -
+		T? -
 		M? {set files_ready 1}
 		_U -
 		U? {
@@ -453,7 +453,11 @@
 		}
 		AM -
 		AD -
+		AT -
+		TM -
+		TD -
 		MM -
+		MT -
 		MD {
 			set file_states($path) [list \
 				_[string index $m 1] \