add ubuntu platform
wp8 add support in level
added ubuntu support
Merge branch 'CB-5243' of https://github.com/pu-chen/cordova-plugin-battery-status into dev
Merged WP8 support for level, but #def'd it out so the same code runs on wp7.  Updated docs to reflect WP8 support for battery level, and low+critical events
Merge branch 'dev' of https://github.com/apache/cordova-plugin-battery-status.git into dev