message: add option to bind the serve to a different host
  This is useful when you are testing/coding your site from a remote host
  for example over ssh.
diff: @@ -32,6 +32,14 @@ pub fn serve_command_args() -> clap::App<'static, 'static> {
  .default_value("3000")
  .takes_value(true),
  )
  + .arg(
  + clap::Arg::with_name("host")
  + .long("host")
  + .value_name("host-name/IP")
  + .help("Host to serve from")
  + .default_value("localhost")
  + .takes_value(true),
  + )
  .arg(
  clap::Arg::with_name("no-watch")
  .long("no-watch")
  @@ -42,8 +50,9 @@ pub fn serve_command_args() -> clap::App<'static, 'static> {
  }
  pub fn serve_command(matches: &clap::ArgMatches) -> Result<()> {
  + let host = matches.value_of("host").unwrap().to_string();
  let port = matches.value_of("port").unwrap().to_string();
  - let ip = format!("127.0.0.1:{}", port);
  + let ip = format!("{}:{}", host, port);
  let mut config = args::get_config(matches)?;
  debug!("Overriding config `site.base_url` with `{}`", ip);
  