Add arg for HTTP server bind address

Eg; `browsh -http-server-bind 127.0.0.1`

Fixes #57

interfacer/src/browsh/browsh.go

@@ -49,6 +49,7 @@ var (
 	IsHTTPServer         = flag.Bool("http-server", false, "Run as an HTTP service")
 	// HTTPServerPort also needs to be exported for use in tests
 	HTTPServerPort       = flag.String("http-server-port", "4333", "HTTP server address")
+	httpServerBind       = flag.String("http-server-bind", "0.0.0.0", "HTTP server binding address")
 	// IsTesting is used in tests, so it needs to be exported
 	IsTesting            = false
 	logfile              string

interfacer/src/browsh/raw_text_server.go

@@ -34,7 +34,7 @@ func HTTPServerStart() {
 	uncompressed := http.HandlerFunc(handleHTTPServerRequest)
 	limiterMiddleware := setupRateLimiter()
 	serverMux.Handle("/", limiterMiddleware.Handler(gziphandler.GzipHandler(uncompressed)))
-	if err := http.ListenAndServe(":" + *HTTPServerPort, &slashFix{serverMux}); err != nil {
+	if err := http.ListenAndServe(*httpServerBind + ":" + *HTTPServerPort, &slashFix{serverMux}); err != nil {
 		Shutdown(err)
 	}
 }