Bug 19510: Add description for edi_manage in acquistion permissions

Bug 19510: Add description for edi_manage in acquistion permissions

Test Plan:
1/ Login
2/ Select patrons
3/ Search for a patron by name or card number that exists in the system
4/ Click More -> Set permissions
5/ Expand 'acquistions' and notice that 'edi_manage' has no description
6/ Apply patch
7/ Refresh the permissions page or repeat steps 2 to 5.
8/ Notice that 'edi_manage' now has a description of 'Manage EDIFACT transmissions'

Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>