Bug 15066: Make transfer rotating collection works under Plack

Bug 15066: Make transfer rotating collection works under Plack

This patch the 2 following errors:
Undefined subroutine &C4::RotatingCollections::transferbook called at
C4/RotatingCollections.pm line 451.
Undefined subroutine &C4::RotatingCollections::GetTransfers called at
C4/RotatingCollections.pm line 450.

And this warning:
"my" variable $colId masks earlier declaration in same scope at
/home/koha/src/rotating_collections/transferCollection.pl line 75.

Test plan:
Create a rotating collection
Transfer it to another branch
It should work with this patch

Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>