Open the app only if it isn't opened

[SrMouraSilva]

• Check if is oppened
  • https://stackoverflow.com/a/46668560/1524997
• Check if is the foreground
  • adb shell dumpsys window windows | grep mCurrentFocus
  • https://stackoverflow.com/questions/28543776/android-shell-get-foreground-app-package-name/45217400