setup enyo bootplate development environment

1. setup nodeJS server
   # npm install express
   # node server.js

   localhost:2000/       >  index.html
   localhost:2000/debug  >  debug.html

2. setup LESS
   see the steps in 'source/Theme.less'

   - In debug.html, uncomment the line referencing "less-<version number>.min.js".
   - In package.js, change "$lib/onyx" to "$lib/onyx/source".
   - Also in package.js, add "Theme.less" (this file).
   - Add variable and rule overrides below.

3. add 'lib/onyx/images' to 'source/'
   fix the problem that index.html couldn't show onyx images
   GET http://localhost:2000/source/lib/onyx/images/xxx.png 404 (Not Found)

4. modify enyo framework
   set the tag of enyo UI button from <button> to <div>
setup phonegap build

* config.xml
  https://github.com/phonegap/phonegap-start/blob/master/www/config.xml

* icon.png
  http://www.knowyourapps.com/wp-content/uploads/2011/11/ICON_Machinarium.png

* PhoneGap BlueTooth Plugin
  https://github.com/don/BluetoothSerial