Improvement to flow of account registration: account verification --> claim username

[PowerChell]

Currently, the users have to claim their username after verifying their account, but many are missing this step since it is not clear/obvious. A few ways this could be improved:

1. adding claiming username to the registration process (if technically possible)
2. creating a pop-up on the screen/link on the page when the account has been verified that sends the user to the claim username page.