def add_envelope_signers(options = {})
      content_type = { "Content-Type" => "application/json" }
      content_type.merge(options[:headers]) if options[:headers]

      uri = build_uri("/accounts/#{@acct_id}/envelopes/#{options[:envelope_id]}/recipients")
      post_body = { signers: options[:signers] }.to_json

      http = initialize_net_http_ssl(uri)
      request = Net::HTTP::Put.new(uri.request_uri, headers(content_type))
      request.body = post_body

      response = http.request(request)
      generate_log(request, response, uri)
      JSON.parse(response.body)
    end
def add_envelope_signers(options = {})
      content_type = { "Content-Type" => "application/json" }
      content_type.merge(options[:headers]) if options[:headers]

      uri = build_uri("/accounts/#{@acct_id}/envelopes/#{options[:envelope_id]}/recipients")
      post_body = { signers: options[:signers] }.to_json

      http = initialize_net_http_ssl(uri)
      request = Net::HTTP::Put.new(uri.request_uri, headers(content_type))
      request.body = post_body

      response = http.request(request)
      generate_log(request, response, uri)
      JSON.parse(response.body)
    end
Public adds signers to a given envelope
 Seehttps://docs.docusign.com/esign/restapi/Envelopes/EnvelopeRecipients/update/

 envelope_id - ID of the envelope to which the recipient will be added
 signers - Array of hashes
           See https://docs.docusign.com/esign/restapi/Envelopes/EnvelopeRecipients/update/#definitions

 TODO: This could be made more general as an add_envelope_recipient method
 to handle recipient types other than Signer
 See: https://docs.docusign.com/esign/restapi/Envelopes/EnvelopeRecipients/update/#examples