fails:File.symlink creates a symlink between a source and target file
fails:File.symlink creates a symbolic link
fails:File.symlink accepts args that have #to_path methods
fails:File.symlink raises an Errno::EEXIST if the target already exists
fails:File.symlink raises an ArgumentError if not called with two arguments
fails:File.symlink raises a TypeError if not called with String types
fails:File.symlink? returns true if the file is a link
fails:File.symlink? accepts an object that has a #to_path method
