IMPROVEMENT (for #1416 : Available items marked waiting as soon as hold is placed)

IMPROVEMENT (for #1416 : Available items marked waiting as soon as hold is placed)

In fact, #1416 is not a bug, it's a feature : SAN-OP librarians place the reserve "book in hand", and confirm on phone that it's available
NPL save the reserve, but pick them from the shelves once a day only. So the item must be "to pull"

This commit improves the behaviour :
- document Reserves.pm a little, it was needed !
- add a systempreference ReservesNeedReturns, that let the library choose it's behaviour
- define the systempref in english & french systempreferences files
- add the systempref through the web installer (bumping to 3.00.00.003)

Signed-off-by: Chris Cormack <crc@liblime.com>
Signed-off-by: Joshua Ferraro <jmf@liblime.com>