Multilingual does not work with multisite

When enabling multilingual on a multisite instance, the database schema is changed (for all domains) but only the first domain has its settings changed to indicate multisite. As a result, the other domains do crash with database errors on every page request.

Fix is not as simple as it sounds as each domain of a multisite instance can have it's own locale (ie. multinational organizations with one CiviCRM domain for each country it serves).

So enabling multisite be done as:

• load the first domain and use the locale to initialize multilingual
• for each additional domain:
• if the locale is already in multilingual, fill $dao->locales and save
• otherwise add the language to the multisite install, fill $dao->locale and save

Note the existing addLocale function will also need to be changed to be multisite friendly, this includes:

• fetching the current Core_DAO_Domain object rather than the first one
• (not quite sure) adding extra locales to all domains rather than only the current

There might be other functions in CRM_Core_I18n_Schema that also need refactoring.