Add support for granting and revoking DB access to Cloud Databases.
Merge branch 'master' into db_grant_access
[google|dns] Add initial support for Google Cloud DNS.

- some common plumbing
- requests for creating, deleting and listing managed zones, with tests
Handle host specification on database users
Merge pull request #3094 from porridge/google-dns

[google|dns] Add initial support for Google Cloud DNS.
[openstack] fix network.rb
create_user, grant_user_access, and revoke_user_access now support host access restrictions
Oops. Added that initializer just so I could pry inside of it. Don't need it now!
Oops another pry call to remove...
Check region against static list, only if host is a subdomain of amazonaws.com
Merge pull request #3101 from elight/db_grant_access

Db grant access
Merge pull request #3109 from fwiesel/region_check_amazon

Check region against static list, only if host is a subdomain of amazonaws
update contributors
Merge pull request #3108 from tnaoto/fix/openstack-network

[openstack] fix network.rb