def config(key)
      capture_io = StringIO.new
      command('config', ['--local', key], nil, capture_io, repository_path.to_s)
      capture_io.string.chomp
    end
def config(key)
      capture_io = StringIO.new
      command('config', ['--local', key], nil, capture_io, repository_path.to_s)
      capture_io.string.chomp
    end
@param [String] key a key to look up in the Git repository configuration.

 @return [String] the value for the given key.