Feat(invite): Adding invite feature.

Feat(email+upgrade): MVP support for user emails (after signup) and
upgrading subscription.

Feat(stripe/billing): cms_billing table complete. NEXT: Allow users to
adjust billing/cancel.

Feat(Big): Added a few things here...

* MVP stripe integration (new controller/server).
* Moved tmpl to views (package v).
* Added ability to create migrations.
* Added first migration. Remove user_to_space in favor of org table.

Feat(*): Project init.