fix bad "licence" names

Mostly what I merged from @lovek323.
Such errors can be easily checked by
  nix-env -f . -qa \* --meta --xml --drv-path --show-trace >/dev/null

pkgs/development/interpreters/renpy/default.nix

@@ -43,7 +43,7 @@ stdenv.mkDerivation {
   meta = {
     description = "Ren'Py Visual Novel Engine";
     homepage = "http://renpy.org/";
-    licence = "MIT";
+    license = "MIT";
     platforms = stdenv.lib.platforms.linux;
   };
 }