Bug 37354: Set maxDate based on issuelength + (renewals * renewalperiod)

Bug 37354: Set maxDate based on issuelength + (renewals * renewalperiod)

This patch sets the flatpickr maxDate in the bookings range picker to
the startdate selected + issuelength + renewals * renewalperiod
circulation rules.

Test plan
1) Set an item in a test biblio to 'bookable' from the items tab.
2) Note the itemtype of the above item
3) Add circulation rules for the above item type, in particular the
   'Loan period', 'Renewals allowed' and 'Renewal period' options.
4) Go back to your biblio and 'Place booking'. Select a user, pickup
   location and item.
5) Open the booking dates flatpickr.
6) Select a start date.
7) Note that the date that is 'Loan period' + 'Renewals allowed' *
'Renewal period' is now greyed out and cannot be selected or any date
beyond it either.

Signed-off-by: Paul Derscheid <paul.derscheid@lmscloud.de>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Katrin Fischer <katrin.fischer@bsz-bw.de>