Make admin and user activation emails more relevant

Currently the email that is sent to board admin when admin activation is enabled and a new user registers has the following text:

The account owned by "test200" has been deactivated or newly created, you
should check the details of this user (if required) and handle it
appropriately.

Surely we can specify exactly one of "deactivated" and "newly created" when sending this email.

Also, instead of "handle it appropriately", how about giving the actual options? E.g. approve/disapprove the account.