Added place cache for search form performance

Base performance improvements:

 * Switch to remote/on-demand place loading from place loading during initial template rendering.
 * Get rid of FormTastic Place display (which it the database 8 times to render the form), replaced with static HTML

Still to-do:

 * Fix single-select/mullti-select issues
 * Hook up good cache invalidation

@Captainkirkdawson, can you take a glance over this (particularly the PlaceCache model, the Places controller, and the foo.task  rake library) and we'll merge it into master and deploy it for the testers?