Preparing release 0.3.0

WIP

Upgrading to the latest version of Phonegap and plugins + moxie-js-client

Remaining work to be done:
 * [x] bump version number
 * [x] test contact plugin (pending API authorisation)
 * [x] use moxie-js-client@master (or tagged version) instead of the testing branch
 * [x] Android test #4 (geolocation w/o cordova plugin)
 * [x] Android check calendar plugin
 * [x] iOS and Android notifications working
 * [x] Prepare CHANGES text for AppStore and Play Store