Fixes issues with Droneshare Uploader service

This PR fixes a couple of issues with the Droneshare uploader service: 
* Network connectivity detection:  the uploader service was listening for network connectivity changes, but it didn't discriminate between connectivity gain/loss and connectivity type updates. As documented @ http://developer.android.com/training/monitoring-device-state/connectivity-monitoring.html#MonitorChanges, `changes to a device's connectivity can be very frequent`, resulting in numerous false restarts of the service.
The update in the PR uses the techniques advocated @  http://developer.android.com/training/monitoring-device-state/manifest-receivers.html#ToggleReceivers to restrict the Droneshare uploader service restarts to actual connectiivty gain/loss events.

* Fixed improper generation, and handling of the notifications for the Droneshare uploader service.