Migrate some configuration into DB

[vphantom]

A simple registry table would do the trick, and could be populated at init time with values currently found in the repo's config.ini. Specifically:

• global.default_lang

• global.languages

• global.name

• global.mail_from

• global.force_outbox

• acl.invited_auto_roles

• acl.registered_auto_roles

• articles.max_daily_articles

• articles.max_authors

• articles.max_keywords

• reviews.accept_days

• reviews.deadline_modifier

This would leave only the obligatory database connection to be edited in config.ini and since we're currently only in SQLite, this might mean no editing at all for most installations.