message: Update error for site and template
diff: @@ -408,7 +408,7 @@ fn run() -> Result<(), failure::Error> {
  let template = if site {
  if template.is_some() {
  - failure::bail!("You cannot specify a template when generating a Workers Site. If you'd like to use the default site boilerplate, run wrangler generate --site. If you'd like to use another site boilerplate, omit the --site when running wrangler generate.")
  + failure::bail!("You cannot pass a template and the --site flag to wrangler generate. If you'd like to use the default site boilerplate, run wrangler generate --site. If you'd like to use another site boilerplate, omit --site when running wrangler generate.")
  }
  "https://github.com/cloudflare/worker-sites-template"
  } else {
  