def archive_to_file(treeish = 'master', prefix = nil, filename = 'archive.tar.gz', format = nil, pipe = "gzip")
      options = {}
      options[:prefix] = prefix if prefix
      options[:format] = format if format
      self.git.archive(options, treeish, "| #{pipe} > #{filename}")
    end
def archive_to_file(treeish = 'master', prefix = nil, filename = 'archive.tar.gz', format = nil, pipe = "gzip")
      options = {}
      options[:prefix] = prefix if prefix
      options[:format] = format if format
      self.git.archive(options, treeish, "| #{pipe} > #{filename}")
    end
Write an archive directly to a file
   +treeish+ is the treeish name/id (default 'master')
   +prefix+ is the optional prefix (default nil)
   +filename+ is the name of the file (default 'archive.tar.gz')
   +format+ is the optional format (default nil)
   +pipe+ is the command to run the output through (default 'gzip')

 Returns nothing