Allow searching events by country etc

[iandunn]

There's an event in Sydney, but searching for Australia doesn't display it. We should be able to get the country name from the Meetup query and include it in the haystack of terms that gets searched for an event.

We may want to include other info, like continent, city (just in case the meetup group name doesn't have it), etc.

Related WordPress/wordcamp.org#1046