Refactored and simplified lua stuff a lot.

assets/ui/test.lua

@@ -1,6 +1,9 @@
-module('ui')
-module('color')
+module('spritebatch')
 
-function draw(x, y)
-  uiDrawRect(COLOR_WHITE, x, y, 32, 32)
+function render(x, y, w, h)
+  spriteBatchPush(
+    nil,
+    x, y,
+    w, h
+  )
 end