Support KILL

[rgchris]

The HTTPd scheme provides a kill? value that if true after processing a request should close that server. This allows for single use, disposable servers such as one designed to obtain OAuth Credentials.

open [
    scheme: 'httpd
    8080 [
        if action = "GET /quit" [
            render "Quitting!"
            response/kill?: true
        ]
    ]
]

Such a feature could be used in the support tests in place of using CALL to end the server process.