Add missing Base module

Author: jderochervlk

src/Base/Base.res

@@ -0,0 +1,11 @@
+// This file is temporary and will eventually replace DOM.res
+
+@editor.completeFrom(Window)
+type window = private {}
+external window: window = "window"
+
+@editor.completeFrom(Event)
+type event = private {}
+
+@editor.completeFrom(EventTarget)
+type eventTarget = private {}