The very draft version of the nrfpp library and sample app.
Fixed the build.
Enhanced the interface: the ctor now gets a parameters which is passed as a context to the callback.
Adding a new base class for simple advertising data types.
 - Added infrastructure and interface for holding and advertising simple data-only properties.
 - Added system event dispatcher, renamed the softdevice event dispatcher to application xxxx
 - Also slightly changed/improved the API, made minor reorganization.
Added a new class derived from BLEAdvertisingData to test the functionality: a simple uint8_t data member is being incremented each 800ms and the new value is being advertised.