Merge pull request Yoctol#26 from Yoctol/release_0.4.0

release 0.4.0

Merge pull request Yoctol#21 from Yoctol/add_vocab_size

add vocab size

Merge pull request Yoctol#14 from Yoctol/word2vec_LSTM

Word2vec lstm

0.2.0

update to 0.1.2