Bug 14127: Typo in message preference form - "mesage"

Bug 14127: Typo in message preference form - "mesage"

This path fixes the typo.

To reproduce and test:
Go to a patron's detail page
The message appears as hint in column-header 'Digests only (i)'

Sponsored-by: Universidad de El Salvador
Signed-off-by: Hector Castro <hector.hecaxmmx@gmail.com>
Signed-off-by: Katrin Fischer <katrin.fischer.83@web.de>
Signed-off-by: Tomas Cohen Arazi <tomascohen@gmail.com>
(cherry picked from commit fba5ce27545fcb5810f32ca42527065958af7f8b)
Signed-off-by: Chris Cormack <chris@bigballofwax.co.nz>