patch 8.0.0780: build failure on Travis

Problem:    Build failure on Travis.
Solution:   Set distribution explicitly. Use Lua and Ruby dev. (Ken Takata,
            closes #1884)

src/version.c

@@ -769,6 +769,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    780,
 /**/
     779,
 /**/