Issue: Install Process No Longer Prompts for Attachment Storage

When installing VaultWiki on vBulletin, the install process no longer prompts the user for what kind of attachment storage should be used. This results in empty values for the attachment settings, and in vBulletin results in attachments being stored in the database.

Database storage is highly discouraged, especially for versioned attachments, and especially for very large wikis. To truly fix this, not only must we restore the missing install step, but we must also provide users with a means of converting from database storage in the next release. This will allow users who are affected by this bug to free up database space and improve their database performance which was almost definitely negatively affected by this bug.