build 73
use NSFetchedResultsController in taxa search
Merge branch 'master' into alex/taxa-search-using-NSFetchedResultsController
delete stale taxa children

this was in the previous implementation, missed it when migrating to
NSFetchedResultsController.
redo object loader results enumeration
fix bug where no results would spin forever
add some comments to taxa search view controller
Merge pull request #102 from inaturalist/alex/taxa-search-using-NSFetchedResultsController

taxa search using ns fetched results controller