Location manager & listener
Added skeleton for location change handling.  most of the UI and
guidanceRoute code will go in the onLocationChange method of the
location handler. Also restructured some of the convienance methods out
of GuidanceRoute and made a new NavigationUtil class for all distance
calculation methods

for more info on android.location see:
http://developer.android.com/guide/topics/location/strategies.html
http://www.vogella.com/tutorials/AndroidLocationAPI/article.html