Bug 4994 - Net::LDAP returns lowercase names

Bug 4994 - Net::LDAP returns lowercase names

This requires us to specify all LDAP mappings in koha-conf.xml in lowercase,
instead of original case used withing LDAP.

Compare readability of

<userid      is="hrEduPersonUniqueID"  ></userid>

(which doesn't work) with required (and non-intuitive)

<userid      is="hredupersonuniqueid"  ></userid>

Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Ian Walls <ian.walls@bywatersolutions.com>
(cherry picked from commit b79c4c88a965a3233f359f8333a492effcf075eb)

Signed-off-by: Chris Nighswonger <chris.nighswonger@gmail.com>