Add explanations to `Create new client`

[liatsade]

https://docs.circuitauction.com/docs/~/drafts/-LQYR3ep_-0IsYg6rNiS/primary/client/how-to-create-a-client

Need to add explanations:

1. Addresses
2. Add screenshot of the client form.
3. Are there other tabs relevant besides the first client tab?