revisions of patch by BWPanda and anonymous5190 in #172646

Fix #685946, original patch by mvc, alternate solution by me: Don't cause a php warning when attempting to load an unsupported country.

Additionally, document the function properly and return success or failure while I'm already here working on it.
(cherry picked from commit 541bba4d96ef3671982072f55374eb3616aa253d)

Killing location_latlon_form(). Sorry, place_taxonomy.module, but this isn't technically part of the external API, and since Location itself doesn't use it, keeping it around is just asking for trouble.

* Implement multiple country autocomplete.
* Allow location_province_code() to operate on an array of countries.
* Extend autocomplete to handle setting specific classes to join country and province fields together -- should be more robust.
* Switch to using views "force single" stuff for country and province filters.
  - If you are having trouble editing country or province filters, please see [#341827]!
* Implement autocomplete for views province filter.

* Fix $op 'delete' on hook_locationapi().
* API CHANGE: Use location_save_locations() with an empty array instead of deleting rows from {location_instance}. This lets us have "real" deletion instead of relying on garbage collection.

Before:
<code>
db_query("DELETE FROM {location_instance} WHERE genid = '%s'", 'mykey:'. $obj->id);
</code>

After:
<code>
$locations = array();
location_save_locations($locations, array('genid' => 'mykey:'. $obj->id));
</code>

* Remove garbage collection routine and UI from settings page. References are checked automatically now.

Further refinement of views support.
Reimplementation of the 'location_directory' default view.
REMOVAL of the 'additional' field -- It is now part of Street.
Fixing sortability in the 'location_table' default view.

Rip out the notion of "supported countries." With the dynamic country loading, this isn't really needed.
This breaks some of the "province listing" stuff, but it needed work anyway.

Thanks!

The location_geocode_meta_tags stuff has been commented out since location.module rev 1.73 from Jan 4 2007. I'm pretty sure it's safe to remove by now. ;)

More moving out of user address thingie.

move some of the megapatch user address book stuff out of the code (into a local file, I still have to take a look at it..)
More LOCATION_PATH removal.

"Fixes" #232632.

Thanks, stephenpickett!

Split out a seperate cache table for the location search cache.

PHEW! One more file to go.