Add API router.
Account for API path without resource.
Add item representation.
Expose file and element text data even if none exist.
Access all available API resources globally.
Make counting records more efficient. Fix #523
Disambiguate references to record type.
Enable index actions.
Add API admin configuration.
Throw HTTP error codes in API controller.
Convert date to UTC, format in ISO 8601. Cast to boolean.
Add GET whitelist. Fix #526
Do not assume all index actions have GET params.
Filter by date since.
Merge branch 'master' into api
Remove per_page as legal index parameter.

Instead, use api_per_page option, set in API configuration.
Merge branch 'master' of github.com:omeka/Omeka into api
Extend record representations. Fix #528
Extend represenations on index action.
Minor fix to array building for extend