Email API change

We have changed the User, Repository and Group REST APIs to no longer return the contact details of a user in an effort to deliver a more trustworthy Bitbucket.

Once a user has validated their email address, you can still perform operations against a user, such as adding someone to a group by their email address.

We appreciate the effort it takes to write and maintain an integration between two systems and apologize for an API change that is not backwards compatible.