updating num_positive_words_this_iter once you get random word

[kanihal]

updating num_positive_words_this_iter once you get random word

[octavian-ganea]

Not very essential, but might introduce bugs, so it's better to fix it. Anyway, this branch will only be reached for very rare entities without any canonical page content and in which all title words are UNK, which should happen very rarely, if never.

[kanihal]

I'm following the exact instruction that is mentioned in the readme of this repo without any modification in the dataset whatsoever, The branch is getting reached quite a lot of times and used to crash there. That's how I found out the variable needs to be updated.

The script data_gen/gen_p_e_m/gen_p_e_m_from_yago.lua used to crash because of % issue not handled properly in LUA52, hence I made another pull request #4 . Does this modification have any effect on control reaching to the branch above?