I have a website project that has more than 50,000 unimportant files (to development) in some directories.
/website.com/files/1.txt
/website.com/files/2.txt
The code below works on deleted as well as modified files to ignore it when you do a git status.
git update-index --assume-unchanged dir-im-removing/
or a specific file
git update-index --assume-unchanged config/database.yml
Ignore modified (but not committed) files in git?
Beware: The suggestion above for deleted files when you do a "git commit -am " includes the deleted file!
A solution that would work for me is to instead of deleting the file, just make it's content blank. This is what I used to mute a .htaccess file.