the most minimal change to be able to disable the initial 2 day upload at start up
added fix for empty receivers - thanks Adrien
Merge pull request #3 from nightscout/feature/initial-upload-pref

I used this for 2 weeks, it's simple workaround till we get the api in place and can do a smart sync
Added comment
Reversed the page reading of the 2 day upload so it reads oldest to newest.
Added Dexcom getSystemTime, getDisplayTimeOffset, and getDisplayTime methods
Added functionality to allow polling of Dexcom be determined by the next expected record received from transmitter instead of being hardcoded to 45 seconds.
Handler clean up to prevent more than one runnable (readAndUpload) at a time.
Removed readAndUpload onDestroy due to exception.
Added new NightScout launcher icons and remove old ones.
Added new icons to be used and changed app name from CGM to NightScout.
Added notification if receiver and Android time are different by > 10 minutes.  Also basic cleanups.
Added warning icon when time between devices mismatches.
Cleanup notification text.
Cleanup notification text again
Changed EPOCH formatter from Janurary to 01.
Added space to notification text to line up Android and Receiver timestamps.
Merge pull request #6 from nightscout/feature/polling-upload-enhance

Feature/polling upload enhancement