'Validates a Flocker configuration contains all required keys and
no unrecognised keys.
:raises ConfigurationError: if any invalid or unsupported keys found.
:returns: ``None``'

def _validate_configuration_keys(self):

    if (u'applications' not in self._application_configuration):
        raise ConfigurationError(u"Application    configuration    has    an    error.    Missing    'applications'    key.")
    if (u'version' not in self._application_configuration):
        raise ConfigurationError(u"Application    configuration    has    an    error.    Missing    'version'    key.")
    if (self._application_configuration[u'version'] != 1):
        raise ConfigurationError(u'Application    configuration    has    an    error.    Incorrect    version    specified.')
