Bug 32610: Add date option to extended patron attributes administration page

Bug 32610: Add date option to extended patron attributes administration page

With this page it will be possible to configure patron attributes
to be a date.

To test:
* Go to administration > patron attribute types
* Add a new patron attribute of type date
  * Dates cannot be repeatable or linked to an AV category, so:
  * Verify, if you check repeatable, date is disabled
  * Verify, if you select an AV category, date disabled
  * Verify, if you check date, AV category and repeatable are disabled
* Save the new patron attribute
* Edit the patron attribute
  * Verify all settings have been kept/stored correctly

Signed-off-by: Philip Orr <philip.orr@lmscloud.de>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>