Keep Untracked Files Handy with a Global .gitignore Pattern

I often find myself in a situation where I have a file that I want to keep around, but don’t want to commit to the repository. Things like notes (todo.txt) or examples (bug_repro.py) or maybe an uncompressed version of an image (banner_xxl.jpg). They could live somewhere outside the source tree, but I like to keep them close to the code they relate to so I don’t forget about them.