Add "GPS found" announcement

[natrius]

There is a "GPS lost" but unfortunately there is not "GPS found" announcement, so if i get the smartphone on my arm and its inconvenient too look at, it would be nice to get that one too.
Or if i just geht out and its cloudy, GPS may need a bit time, so i just walk until it will find the GPS (Counter also starts when GPS is found for the first time)