PlaceDataSource and EventDatasource now have the concept of _enabled_
This allows data sources to not be shown on the Map and Calendar pages, e.g. to temporarily disable them for whatever reason (experimental, temporary outage).

- admin editing panels
- setup.php for initial table
- site.php filters by this field in the calendar() and map() handlers

Also, fixed minor wording/typo on admin page for EventDataSource.
Removed CSV driver for PlaceDataSource; no existing use case for it, so no immediate plans to develop it.
Minor change to help text in ArcGIS REST driver, as it does support both Point and Polygon now.

Stub entry for OGC WFS driver for PlaceDataSource
Numerous changes today, some cosmetic and some more deeply functional:

* Cosmetic changes to Admin panels, wrapping things in tabs and containers for a consistent look and feel between pages.

* Cosmetic changes: added tablesorter into the mix, made admin panel tables sortable.

* Created concept of Places being in Categories (PlaceCategory). This is a many-to-many relation, so akin to "tags" and not "folders" Implementation of PlaceCategory involved changes to the PlaceDataSource driver specification, and the new attribute_json where raw attributes can be stored for later recall (e.g. analyzing the record for categorization/tagging). ArcGIS REST driver was updated tio suit.