patch 7.4.1649

Problem:    The matchit plugin needs to be copied to be used.
Solution:   Put the matchit plugin in an optional package.

src/version.c

@@ -748,6 +748,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1649,
 /**/
     1648,
 /**/