Quick Settings Form UX tweaks [#3026627]

Since you use the word "client" to denote some of the credentials, I think you could use the word "host" to denote the other credentials.
The url /admin/alexanders leaves a lot to be desired. Thankfully not all modules just drop their settings page at the root of admin. We should put it inside "config" and maybe the sub-section "web services" and also make sure it appears in the menu system.