Add dim and underline as Select Graphic Rendition (#442)

Author: utix

diff-so-fancy

@@ -910,6 +910,14 @@ sub git_ansi_color {
 		push(@ansi_part, "1");
 	}
 
+	if (grep { /dim/ } @parts) {
+		push(@ansi_part, "2");
+	}
+
+	if (grep { /ul/ } @parts) {
+		push(@ansi_part, "4");
+	}
+
 	if (grep { /reverse/ } @parts) {
 		push(@ansi_part, "7");
 	}