def container(path)
      parts = path.split('.', 2)
      match = (self[parts[0].to_s] || self[parts[0].to_sym])
      if !parts[1] or match.nil?
        self
      else
        match.container(parts[1])
      end
    end
def container(path)
      parts = path.split('.', 2)
      match = (self[parts[0].to_s] || self[parts[0].to_sym])
      if !parts[1] or match.nil?
        self
      else
        match.container(parts[1])
      end
    end
Return the containing Hashie::Mash of the given dotted path

 @param [String] path

 @return [Hashie::Mash, nil]