Remove annoying trailing whitespace from files.
Warning: this is alpha-quality code written with the assistance of several glasses of gin. It's entirely possibly that it may eat your files, your children, or your future, and I disclaim responsibility for any of that.
RubyGems:
$ gem install whiteout
$ whiteout -h
$ echo -e "foo \nbar" | whiteout
foo
bar
$ whiteout file1.rb file2.rb # modified in place