Added Default org and loc selection support to users.

We now have support for `default_org` and `default_loc`,
selection under the org and loc tabs for the users.
Merge pull request #1629 from kbidarkar/user-default-org

Added Default org and loc selection support to users.
Test to check if the activation-key's content-host limit actually limits its usage
Merge pull request #1630 from sghai/ak-limit-test

Test to check if the activation-key's content-host limit actually limits its usage