[BUGFIX] Fix recurrance subtype proc func

The non existing class name is removed from the TCA itemsProcFunc
configuration, the class name is updated to
\Tx\CzSimpleCal\Utility\EventConfig and the getSubtypes() method
in the different recursion type classes is not called statically any
more.
[!!!][TASK] Moved EventStatus do Enumeration namespace
[!!!][FEATURE] Enhanced / restructured exception handling

The database model for the exceptions has changed and is now more
integrated into the Extbase data handling. Exceptions are now attached
as inline elements to events and exception groups to make the usage
easier for editors.

A new exception type is introduces that allows overwriting event
properties for the exceptional events. E.g. an event can now be
marked as "Cancelled" on a certain date within a recurring event series.
[TASK] Restructured data handler hook

The data handler hook will now also index events, when a related
exception record is edited.

The functionality from the processCmdmap_postProcess() method is now
moved completely to the processCmdmap_preProcess() method.

The detection if event properties have changed is fixed and improved.

TODO: Also update related events when exception groups are changed.