Add .gitignore
Added a .gitignore file in order not to sync the .idea config folder.
Please note that git.rz.uni-jena.de is deprecated and will be disabled on October 1. Please update your repo URLs if git.rz.uni-jena.de is still used.
You can check it with "git remote -v" for each repo, and change it with "git remote set-url origin git.uni-jena.de", if necessary.
Added a .gitignore file in order not to sync the .idea config folder.