CB-5114 Append Windows 8.1 into plugin.xml + Optimize Windows 8 Geolocation proxy
CB-5114 Windows 8.1 - Use a new proxy as old geolocation methods is deprecated

* Added separate section for Windows Univeral Apps
* Made GeolocationProxy compatible with windows8.0 and 8.1 api versions
update GeolocationProxy.js
Renamed test dir, added nested plugin.xml
CB-7244 Updated version and RELEASENOTES.md for release 0.3.9
CB-7244 Incremented plugin version.
Merge branch 'CB-7146' of https://github.com/stacic/cordova-plugin-geolocation
Merge branch 'CB-5114' of https://github.com/sgrebnov/cordova-plugin-geolocation
this closes #5, #3
Merge renamed tests dir