* Allow payment amounts to be partial per invoice paid
* edge case tests for payments
* Allow per invoice payment amounts and allow direct payments which simply credit a clients credit_balance
* Fixes
* Fixes for Store Payment Validation
* Tests for Payments
* Use custom validator to ensure payments are made ONLY to payable invoices
* Working on custom payment validators
* Update Client balance
* fixes for client balance
* Fixes for activity API
* Provide failsafe creation of invoice invitations
* URL Links for invitations
* open up route for invitations
* Set DB by Invite
* Set DB By invitation Key
* Tests for setting DB based on user email address
* Middleware for setting db by email address
* fixes for tets
* fixes for tests
* Tests for bulk actions
* Payments API
* Fixes for tests
