Don't load ActiveRecord during rails initialization

[jdelStrother]

If ThinkingSphinx requires ActiveRecord on load, then setting configuration in applications' initializers with have no effect (eg Rails.application.config.active_record.has_many_inversing).

Instead, ActiveRecord should be deferred to the end of initialization using the Railtie. WDYT to something like this?

[pat]

Looks good to me - and thanks for figuring out the fix! Must have been a frustrating thing to debug.