Split out Authenticator's constructor "path" parameter into "clientHost" and "clientPath"

[g105b]

This has caught me out more than once while building Authwave. I see currentPath, so I provide it with $this->server->getRequestUri(), but the provider actually requires the host too, to load the correct settings on the provider's database. This could be fixed by changing the name of the parameter to indicate that the full path with host is required, but would be cleaner to provide it as two parameters.