generalized usage of event throughout specs

previously: event was created explicitly in a number
of locations.

now: modifying the event model / its factory will
be sufficient to make tests pass.  
Drop precompiled assets.
Keep navbar from clobbering page titles.
Use Select2 to add autocomplete support to user and location dropdowns.
Merge branch 'select2' of git://github.com/faulkner/bridge_troll into faulkner-select2
Merge branch 'event_specs' of git://github.com/michaelglass/bridge_troll into michaelglass-event_specs