Do not use setuptools to install lutris
Remove install_requires from setup.py
Remove hide_panels system option
Add help messages for xboxdrv and killswitch
Fix #92: First right-click fails in List view
Confine the double click simulator to Grid view (fix #88)
Fix fat blank space added when switching view

"The add_with_viewport() method is used to add a widget without native
scrolling capabilities to the scrolled window. [...] This will be
wrong for most widgets that support native scrolling."

The TreeView and IconView both having native scrolling capability,
there came the glitch.
Refresh downloaded icons in Grid view (fix #87)
Reworked get_game_path() and browse_dir() in wine runner

Made get_game_path() just return the prefix path or global path and
moved the things specific to browse_dir() for wine in browse_dir().
Fix get_browse_dir() returning game.directory
Create working_dir base
working_dir for Linux runner
working_dir for Dosbox
Refactor: Make use of new game_exe property
Remove self.game_path remains
Remove some leftover get_game_path
Remove unused stuff in Runner
Fix Linux.play() using relative path for the executable
Add working_dir setting to Wine and Linux runners
Docstrings cleanup