updated for version 7.3.871

Problem:    search('^$', 'c') does not use the empty match under the cursor.
Solution:   Special handling of the 'c' flag. (Christian Brabandt)
            Add tests.

src/version.c

@@ -728,6 +728,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    871,
 /**/
     870,
 /**/