[Pianod] Web client parameters

[Perette Barella]

The web client now accepts two parameters:

server: pre-populates the "Server" field.
login: if set to "auto", automatically logs in.  If a username/password have been stored via the save password checkbox, it uses those.  If it remembers a username but not a password, login fails and it stays on the login screen.  If neither is set (or they're set to empty strings), it uses a guest login.

After using this, the recorded server is updated.  I'm not sure if that's the Right Thing, so it may change.

http://deviousfish.com/pianod/client/?server=house:4446&login=auto

Perette