filter which draft pages are in which draft books
allow contained_in to be stored/modified
update expected json results
don't dump dev db
make containment based retrieval work
update containment info for documents when binder is stored
fix travis config to work w/ new test db name
use existing utlity function to get documents - careful to iterate only once
cleanup args processing for contained_in case
move util method to utils
expose underlying storage Error class, for rollback/abort
complete moving update_containment to utils
explain bare except in utility method