Version 1.2.0

WHAT'S NEW v1.2.0:
* Altitude functionalities (altitude, ascent, ascent rate, slope)
* Multipages pebble application (use the middle button to change the current page)
* Improved stability

BUGFIXES:
* speed display (missing separator & wrong alignment)
* saved distance & average speed
* Foreground service (add a notification in the status bar and therefore prevents the app to be killed by android when low on memory)