WebDeposit: collection and title addition

* Adds collection to the configuration. If it is not configured, the
  name of the deposition is assumed as the collection.

* Fixes the key for title field's cook function.

Tested-by: Tibor Simko <tibor.simko@cern.ch>
WebDeposit: optional ckeditor & date format

* Removes optional ckeditor from configuration.

* Changes datepicker's date format to yyyy-mm-dd

Reviewed-by: Tibor Simko <tibor.simko@cern.ch>