def edit_subscription(ac, s, t=nil, a=nil, r=nil)
      query = {:T => @auth_token, :ac => ac, :s => s}
      query[:t] = t unless t.nil?
      query[:a] = a unless a.nil?
      query[:r] = r unless r.nil?
      Helper.request '/reader/api/0/subscription/edit', {:query => query}, :post
    end
def edit_subscription(ac, s, t=nil, a=nil, r=nil)
      query = {:T => @auth_token, :ac => ac, :s => s}
      query[:t] = t unless t.nil?
      query[:a] = a unless a.nil?
      query[:r] = r unless r.nil?
      Helper.request '/reader/api/0/subscription/edit', {:query => query}, :post
    end
edit subscription
 @param [String] ac action ('edit' or 'subscribe' or 'unsubscribe')
 @param [String] s stream id(feed/feed_url)
 @param [String] t subscription title. Omit this parameter to keep the title unchanged
 @param [String] a add subscription to folder/tag.
 @param [String] r remove subscription from folder/tag.