Bug 12876 - Reserve in waiting/transfer status may be cancelled by user

Bug 12876 - Reserve in waiting/transfer status may be cancelled by user

User may cancel his own reservation at waiting or in transit status
through calling opac-modrequest.pl. Cancel button is disabled in
interface but possibility to cancel should be checked also in
opac-moderequest.pl, before calling CancelReserve().
Similar situation is with opac-modrequest-suspend.pl

This patch provides new soubroutine to chceck if user can cancel given
reserve. It's possible only when he's owner of hold and hold isn't in
transfer or waiting status.

Additionaly there are new test for this function in Reserves.t

Signed-off-by: Jonathan Druart <jonathan.druart@biblibre.com>
Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Passes all tests, QA script and new tests.
Works as described, tested with:
.../cgi-bin/koha/opac-modrequest.pl?reserve_id=XXX

Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>