Add gzip compresion and emergency contact

The ride files will now be .json.gzip
Users will also now be able to add an emergency contact phone number.
Ride logger will use that number to update the contact on the riders current
location.  It will also notify them if the acceleration is above 15 or m/s^2.
If so the emergency contact will get an sms with the current location.

TODO:  15m/s^2 is easy to trip.  I need to research a way to minimize false positives.