plugin.xml: Adding platform tizen.
src/tizen: Adding DeviceProxy.
 Incremented plugin version on dev branch.
Delete stale test/ directory
supported platforms updated
Merge branch 'tizen' of http://github.com/siovene/cordova-plugin-device into dev
CB-5980 Updated version and RELEASENOTES.md for release 0.2.8
Merge remote-tracking branch 'cordova/master' into dev