Add support for hosts/ports/passwords

[Billiam]

It would be nice to have support for notification host for notification types that support it (ex: gntp)

[jugyo]

Do you have any idea about the API?

[mattn]

I guess that it may make addhok codes. For sending notify to remote, some growler require hosts/port/password, but others may not. And user don't know what growler was chosen by notify.
I'm author of Growl::Any that is a perl module similar to notify. I had get same problem.

[kristianfreeman]

@jugyo, @mattn – are you both interested in pursuing this issue still?