Splitscreen Mod 0.3.0

Lots of new good stuff! As always, the download link is below the text. Make sure you read the README, if you haven't read the one from the 0.2.0 release.

Changelog:

• the game settings are not replicated in the alpha
  gui anymore. The host window will stay open
  until you manually click the 'Start' button, so
  you can configure it there.
• all network windows except for the one from the
  host are hidden now
• added some mod options: you can choose if the windows
  should be merged at all (disable this if you can't
  get it to work otherwise), how long the mod should
  wait before merging and if the taskbar should be
  hidden (also new!)
• all options in the GUI get saved and load from the
  settings .ini file automatically
• added 4:3 aspect ratio layouts for all player counts.
  this is a trade of between having blank space and
  working camera when driving. In the future, we might
  be able to fix the camera for non 4:3 ratios.
• sound should always play in all windows, even on wine
  now. if it doesn't it is possible to press F3 to
  force it again (useful when you gave and removed
  focus manually). Thanks to @sqozz for figuring this out!
• new icon