After some profiling, give all modules a common prototype.

common/modules/io.jsm

@@ -12,8 +12,7 @@ try {
 Components.utils.import("resource://dactyl/bootstrap.jsm");
 defineModule("io", {
     exports: ["IO", "io"],
-    require: ["services"],
-    use: ["config", "help", "messages", "storage", "styles", "template", "util"]
+    require: ["services"]
 }, this);
 
 // TODO: why are we passing around strings rather than file objects?