DistanceMatrix: use latitude/longitude

use latitude/longitude ( north/east ) to query Google Maps instead of
full text search (possible mistakes with the latter, p.e. Déchetterie de
Woluwé Saint-Pierre, Val des Seigneurs 146, 1150 Woluwé Saint-Pierre,
België => Google takes Saint-Pierre instead of Woluwé Saint-Pierre,
quite a difference)