def download_manifest(sftp)
      FastlaneCore::UI.message('Checking remote Manifest')
      json = nil
      remote_manifest_path = remote_manifest_path(appcode)
      begin
        sftp.stat!(remote_manifest_path) do |response|
          if response.ok?
            FastlaneCore::UI.success('Loading remote manifest:')
            manifest = sftp.download!(remote_manifest_path)
            json = JSON.parse(manifest)
          end
        end
      rescue
        FastlaneCore::UI.message('No previous Manifest found')
      end
      json
    end
def download_manifest(sftp)
      FastlaneCore::UI.message('Checking remote Manifest')
      json = nil
      remote_manifest_path = remote_manifest_path(appcode)
      begin
        sftp.stat!(remote_manifest_path) do |response|
          if response.ok?
            FastlaneCore::UI.success('Loading remote manifest:')
            manifest = sftp.download!(remote_manifest_path)
            json = JSON.parse(manifest)
          end
        end
      rescue
        FastlaneCore::UI.message('No previous Manifest found')
      end
      json
    end
Downloads remote manifest, self.appcode required by options.

 @param sftp
 @param [String] remote_path
 @returns [JSON] json or nil