Autocomplete matches more spellings and drops duplicate addresses

Autocomplete now matches a completed street word against any spelling the sources use, and returns one address once even when more than one source carries it.

• A completed street type or direction now matches any of its spellings, so 9 Ave SW, 9 Av SW, and 9 Avenue Southwest all find the same address.
• An address held by more than one source now comes back once instead of several times.