Establish a month of free trial

Summary:

• New registrations get all the bells and whistles
• Do not bill entitlement's first month compared against the wallet's creation date

Test Plan: None

Reviewers: #hkccp_developers, machniak

Reviewed By: #hkccp_developers, machniak

Subscribers: machniak, #hkccp_developers

Differential Revision: https://git.kolab.org/D1504