Support ctrlp_custom_ignore as function ref

Author: mattn

autoload/ctrlp.vim

@@ -1527,13 +1527,17 @@ endf
 
 fu! s:usrign(item, type)
 	if s:igntype == 1 | retu a:item =~ s:usrign | end
-	if s:igntype == 4
+	if s:igntype == 2
+		if call(s:usrign, [a:item, a:type])
+			retu 1
+		end
+	elsei s:igntype == 4
 		if has_key(s:usrign, a:type) && s:usrign[a:type] != ''
 					\ && a:item =~ s:usrign[a:type]
 			retu 1
 		elsei has_key(s:usrign, 'func') && s:usrign['func'] != ''
 					\ && call(s:usrign['func'], [a:item, a:type])
-			retur 1
+			retu 1
 		end
 	end
 	retu 0