def fs_move(from, to)
      FileUtils.mv(File.join(self.git_dir, from), File.join(self.git_dir, to))
    end
def fs_move(from, to)
      FileUtils.mv(File.join(self.git_dir, from), File.join(self.git_dir, to))
    end
Move a normal file
   +from+ is the relative path to the current file
   +to+ is the relative path to the destination file

 Returns nothing