def revoke_token
      # entry point
      url = "#{@client.app_info[:launcher_server]}#{API_VERSION}/auth"

      # api call
      uri = URI(url)
      http = Net::HTTP.new(uri.host, uri.port)
      req = Net::HTTP::Delete.new(uri.path, {
        'Authorization' => "Bearer #{@client.key_helper.get_valid_token()}"
      })
      res = http.request(req)
      res.code == "200"
    end
def revoke_token
      # entry point
      url = "#{@client.app_info[:launcher_server]}#{API_VERSION}/auth"

      # api call
      uri = URI(url)
      http = Net::HTTP.new(uri.host, uri.port)
      req = Net::HTTP::Delete.new(uri.path, {
        'Authorization' => "Bearer #{@client.key_helper.get_valid_token()}"
      })
      res = http.request(req)
      res.code == "200"
    end
Revoke the authorisation token obtained from SAFE Launcher.

 Usage: my_client.auth.revoke_token()
 Fail: false
 Success: true

 Reference: https://maidsafe.readme.io/docs/revoke-token