Extend the API with new methods

[Oxalin]

Since we are support specifically the "hidden" argument, and because we support adding extra arguments (whatever please the developers), we could extend the API to provide a way to get some values.

Would proposing the following methods make sense:

• openAsHidden() which would return a boolean telling wheteher the app is set to be launched as hidden/in background. It could mimic the method proposed by electron and extend it to all supported platforms.
  • See https://github.com/Teamwork/node-auto-launch/issues/58 for a usecase
  • Should we care if it was launched at login or system wide (if we ever support this option)?
• getArguments() (or getExtraArguments()) would return an array of all the arguments sent to the app at autolaunch.
• toggle() to take care of the logic to enable ou disable autolaunch
  • https://github.com/Teamwork/node-auto-launch/pull/121
• extend disable() method to remove enabled/disabled state in Windows registry.
  • usecase: https://github.com/Teamwork/node-auto-launch/issues/22