'Get several apps details from a list of package names.
This is much more efficient than calling N times details() since it
requires only one request.
packageNames is a list of app ID (usually starting with \'com.\').'

def bulkDetails(self, packageNames):

    path = 'bulkDetails'
    req = googleplay_pb2.BulkDetailsRequest()
    req.docid.extend(packageNames)
    data = req.SerializeToString()
    message = self.executeRequestApi2(path, data, 'application/x-protobuf')
    return message.payload.bulkDetailsResponse
