Use a semaphore instead of a boolean to dictate whether we fire off a request operation or just use the cached copy.

Signed-off-by: Blake Skinner <bskinner@mit.edu>
Remove the feature layer bits. We don't need them yet so no need to jump the gun.

Signed-off-by: Blake Skinner <bskinner@mit.edu>
Tweak the sync code so it can safely be called either on a background queue or the main queue. Also move the sync onto the main queue; it makes the annotation updates a bit smoother.

Signed-off-by: Blake Skinner <bskinner@mit.edu>
Clear out a pending callout, if it exists and there is no active callout.

Signed-off-by: Blake Skinner <bskinner@mit.edu>
Fix the annotation ordering so polygons/lines are sorted below markers

Signed-off-by: Blake Skinner <bskinner@mit.edu>
IPHONEAPP-657

Fix the offset calculations; they were really off. This should prevent the MIT shuttles from pretending they are duck boats.

Signed-off-by: Blake Skinner <bskinner@mit.edu>