IdentityProvider persistence, tests, creating a new zone creates an internal IdP
with origin_key='uaa'

[#82406674]
https://www.pivotaltracker.com/story/show/82406674
Change unique key constraint on users from 'username+origin' to 'username+identity_provider_id'
 - Users can now be created with the same username if they are in different IDPs.

[#82406674] https://www.pivotaltracker.com/story/show/82406674

Signed-off-by: Rob Szumlakowski <rszumlakowski@pivotal.io>
Add subdomain to activation links in emails.

[#82406674]
Fixing variances in database vendors

[#82406674]
Running ID column cleanup at the very end so we can keep writing mysql
migrations the same way (varcahr(36))
Zonifying client update and delete queries. Need to change the pk of
oauth_client_details to be (client_id,identity_zone_id) to allow the
same client_id to be in different zones.
[#82406820]
https://www.pivotaltracker.com/story/show/82406820
Bootstrapping clients to a new IdentityZone in the create identity zone
api call
[#82406820]
https://www.pivotaltracker.com/story/show/82406820