Merge pull request #121 from nightscout/kl.readdatatocore

Migrating ReadData to the core module
Initial pass at device abstraction
Migrating to Wire for protobuf implementation
Removing commented code
Merge remote-tracking branch 'origin/kl.deviceabstraction' into kl.deviceabstraction

Conflicts:
	app/src/main/java/com/nightscout/android/SyncingService.java
Merge branch 'dev' into kl.deviceabstraction
Merging with device abstraction branch
Merge branch '76-kl.mqtt' into 76-kl.mqttui
Fixed bug where SGV time was reported incorrectly
Added boundary checking to avoid unwanted exceptions