A user can type in their existing name in the registration flow. Status can
confirm if they own it. After signing a transaction, the user can update the
Whisper ID to their new one.
Instead of using a hardcoded contract for stateofus, the standard `owner`
method is called to find the resolver contract of a ens name.
This allows users to set the pubkey even for ens names that are not
subdomains of stateofus
Signed-off-by: yenda <eric@status.im>
7b6dfad702