Integrate navigation voice capability use

Add code to pull in the voice capabilities binding, subscribe to the
existing setDestination and cancelNavigation events, and use the data
that comes from them to set/clear the destination waypoint.

Bug-AGL: SPEC-3107

Signed-off-by: Scott Murray <scott.murray@konsulko.com>
Change-Id: Iaeb0283492cc89e8cff1a1558cab7554e32e3142