Bug 11263: do not use system locales settings for subscriptions

Bug 11263: do not use system locales settings for subscriptions

The locales list for subscriptions should not be retrieved from the
locales of the system.
This patch retrieves the locales list from the Koha DB (in the same way
as pref language and opaclanguages).

Test plan:
Edit a subscription (or a numbering pattern) and verify the list of
languages is the same as languages available in Koha.
Note: with this patch we loose the saeson translation, it is
normal. See report linked.

Signed-off-by: Bernardo Gonzalez Kriegel <bgkriegel@gmail.com>
Work as described. No koha-qa errors.

New locale is retrieved from installed languages.
I wonder if that list can be restricted to
'enabled' ones (parsing syspref language value).

Signed-off-by: Katrin Fischer <Katrin.Fischer.83@web.de>
Passes QA script and all tests.
Works according to description.

Signed-off-by: Galen Charlton <gmc@esilibrary.com>