Send a verification emails on account creation and deletion

[jfederico]

When a users signs up or deletes their account the user does not have a way to verify that the account was created or deleted.

There is a request for email verification if the GL server is configured for local accounts and/or KC (or any external authentication broker or provider) has it enabled, but that is only for local accounts. If the user uses Google or Office365 or any other social authentication method, the account is simply created.

There have been some complaints of people thinking that their account was not deleted because they sign in, delete, and sign in again. The account was indeed deleted, and all the rooms disappeared, but a new account is created in the second sign in.

A simple solution would be to send a confirmation email when the new account is created or if the account is deleted.