Adding support of street/associatedStreet relations for address search

Have added support of associatedStreet and street relations for addresses (see ticket http://code.google.com/p/osmand/issues/detail?id=1272). 

Unfortunately, had no chance to verify it was working correctly (see https://groups.google.com/forum/?fromgroups=#!topic/osmand/GN3NICMc7rU), but it does not introduce any exceptions, not breaking current functionality, and output file is bigger - contains more address data for my region.