message: Change open_browser to open browser in child process
diff: use std::process::Command;
  pub fn open_browser(url: &str) -> Result<(), failure::Error> {
  - let _output = if cfg!(target_os = "windows") {
  + if cfg!(target_os = "windows") {
  let url_escaped = url.replace("&", "^&");
  let windows_cmd = format!("start {}", url_escaped);
  - Command::new("cmd").args(&["/C", &windows_cmd]).output()?
  + Command::new("cmd").args(&["/C", &windows_cmd]).spawn()?;
  } else if cfg!(target_os = "linux") {
  let linux_cmd = format!(r#"xdg-open "{}""#, url);
  - Command::new("sh").arg("-c").arg(&linux_cmd).output()?
  + Command::new("sh").arg("-c").arg(&linux_cmd).spawn()?;
  } else {
  let mac_cmd = format!(r#"open "{}""#, url);
  - Command::new("sh").arg("-c").arg(&mac_cmd).output()?
  + Command::new("sh").arg("-c").arg(&mac_cmd).spawn()?;
  };
  Ok(())
  