Bug 11580 - If returnBeforeExpiry is ON, use calendar to calculate return date not...

Bug 11580 - If returnBeforeExpiry is ON, use calendar to calculate return date not on closed day (depending on useDaysMode)

Test plan:
1. ReturnBeforeExpiry is activated
2. useDaysMode is different from "circulation rules only"
3. Set expiry date of a patron to a near date
4. Set a closed day on calendar for this date
5. Do a checkout

Without patch, return date will be patron expiration date
With the patch, return date will be last open day before patron expiration day

Signed-off-by: Claire Gravely <claire_gravely@hotmail.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>