patch 7.4.1976

Problem:    Number variables are not 64 bits while they could be.
Solution:   Add the num64 feature. (Ken Takata)

src/version.c

@@ -455,6 +455,11 @@ static char *(features[]) =
 #else
 	"-netbeans_intg",
 #endif
+#ifdef FEAT_NUM64
+	"+num64",
+#else
+	"-num64",
+#endif
 #ifdef FEAT_GUI_W32
 # ifdef FEAT_OLE
 	"+ole",
@@ -753,6 +758,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    1976,
 /**/
     1975,
 /**/