Bug 25364: Add "Other" to the gender options in a patron record

Bug 25364: Add "Other" to the gender options in a patron record

This patch adds "Other" as an option, and also changes the wording of
"None specified" slightly.

To test:

1) Apply the patch
2) Check that there is an "Other" radio button in the patron record, and
that the wording of "None specified" has changed to "None specified /
Prefer not to say".
3) Check that you can save changes to the gender of this patron record,
both on create and modify.
4) Check that these changes also work in the Opac Self-Registration
functionality.

Correct typos in previous commit

Signed-off-by: Devinim <kohadevinim@devinim.com.tr>
Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>