Prevent Lutris window to open when running a game from command line.
The opening window seems to be a regression introduced by commit dabf7ef
which was a revert of commit 7ca5f6c9. Adding back chunks of commit
7ca5f6c9 prevent the Lutris window from opening when running game from
command line.
Also removing a duplicate entry from the .gitignore file and adding
JetBrains IDE projet directory.