Try to reduce the frequency of unnecessary updates by keeping a copy of the last set of new annotations that were updated and making sure we aren't doing the same thing twice.
Try to reduce the frequency of unnecessary updates by keeping a copy of the last set of new annotations that were updated and making sure we aren't doing the same thing twice.

Signed-off-by: Blake Skinner <f2809f73afc906ecbb5ce29ea24012b18700bcc7@mit.edu>

smartcop/MIT-Mobile-for-iOS,xNUTs/MIT-Mobile-for-iOS,MIT-Mobile/MIT-Mobile-for-iOS,MIT-Mobile/MIT-Mobile-for-iOS,xNUTs/MIT-Mobile-for-iOS,smartcop/MIT-Mobile-for-iOS