Bug 9021: Flag issues

Bug 9021: Flag issues

Check in and check out were failing for me.
Specificly, the $borrower->{flags}->{...} was not accessible as
a hash, so I put a hash ref check around the code that would fail.

TEST PLAN
---------
1) Attempt a checkout
   -- blows up with "1" not being allowed as a hash ref.
2) Apply patch
3) Attempt same checkout again
   -- success
4) prove -v t/db_dependent/Circulation_dateexpiry.t
   -- this triggers CanBookBeIssued
   -- this should succeed
5) prove -v t/db_dependent/rollingloans.t
   -- mine skipped the tests, but if configured, it
      should also trigger and succeed.
6) run koha qa test tools

Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Mark Tompsett <mtompset@hotmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>