Bug 17252 - Koha::AuthorisedValues - Remove GetAuthorisedValueByCode

Bug 17252 - Koha::AuthorisedValues - Remove GetAuthorisedValueByCode

The subroutine C4::Koha::GetAuthorisedValueByCode returned the
description (staff or opac) for a given authorised value.

Note that we may need a unique key to ->find instead of ->search.

Test plan:
- Checkin an item that cannot be checked in because it's lost, the
  message should display the AV description
- Generate a letter with borrowers.streettype equals an ROADTYPE AV, the
  description should be displayed.
- Edit a patron attribute type, the AV dropdown list should be
  displayed
- Create the PA_CLASS AV category (see bug 7154) and make sure it
  behaves as before when editing a patron
- The checkout list should display descriptions for LOC, LOST and
  DAMAGED

Signed-off-by: Claire Gravely <claire_gravely@hotmail.com>

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>