Test Event#search, at least when using SQL search engine.
refactor Event.search.
postgresql requires venues.id to be in the GROUP BY, for whatever reason.
ensure correct order of search results when its germane to the test, ignore it when its not.
simplify Event#search limit option test.
prefer Hash#fetch to conditional.
abuse arel#where_values to clean up progressive search query building in Event#search.
Merge pull request #106 from botandrose/test_event_search

Test and refactor Event#search.