Get an entity's full id provided a partial one.

        Raises EntityNotFound if partial cannot be resolved.
        @param partial The partial id (e.g. mysql, precise/mysql).
        @param channel Optional channel name.

def entityId(self, partial, channel=None):
        '''Get an entity's full id provided a partial one.

        Raises EntityNotFound if partial cannot be resolved.
        @param partial The partial id (e.g. mysql, precise/mysql).
        @param channel Optional channel name.
        '''
        url = '{}/{}/meta/any'.format(self.url, _get_path(partial))
        data = self._get(_add_channel(url, channel))
        return data.json()['Id']