Function sample

V1 version of: sample outputs from a model, and do it all at once :param news_config: Configuration used to construct the model :param initial_context: [batch_size, seq_length] that we'll start generating with :param eos_token: Stop generating if you see this (tf scalar) :param

(news_config: GroverConfig, initial_context, eos_token, min_len, ignore_ids=None, p_for_topp=0.95,
           do_topk=False)