Allow to create content with any language from LANG_INFO instead of AVAILABLE_LANGUAGES
Now we are only allowing to create content (blog, document, …) with a language defined in the AVAILABLE_LANGUAGES setting.
It's not scalable because we are not adding all languages to this settings.
Instead we should allow any languages from the ones in django.conf.locale.LANG_INFO
.
Thought, we should not display all those languages in the select of the form, or if we do so we should have a way to either put some languages on the top (defined from a per box setting) of the list or easily search in the list.
In the case where we only display some languages in the select, we should not override the language when editing a document which as another language.
We should then allow languages code with more than 2 letters in the db (cf #356 (closed)).
AVAILABLE_LANGUAGES should then be used only for the available translations of the ideascube front (so the dropdown select in the footer).