MXS-1300: Un-modularize the core

Making the core a module proved to bring more problems than it solved. For
the sake of simplicity in installation and code coverage reporting, the
core is now completely contained in the `lib/` directory.

Also added preliminary coverage reporting with nyc.

maxctrl/maxctrl.js

@@ -13,7 +13,7 @@
 
 'use strict';
 
-var maxctrl = require('maxctrl-core')
+var maxctrl = require('./lib/core.js')
 
 // Mangle the arguments if we are being called from the command line
 if (process.argv[0] == process.execPath) {