More dynamic EditableColumns

- All editableOptions are now applied to the jQuery editable() call
unless they are closures, in which case they are used to populate a
data-* tag for each row
- It is now possible to pass JsExpressions in editableOptions, which are
editable treats as functions (e.g., "display")
- Removed format = raw, which was stopping values from being formatted
by renderDataCellContent (for instance [date, 'j/n/y'])