Fix some problems

[ufownl]

Thank you for your excellent work, but I ran into some problems while trying to use it. That's why I create this PR.

This PR should solve three problems:

1. Remove *.pyc files and ignore the unnecessary files by adding .gitignore file;
2. Fix the dependencies decay by adding requirements.txt file;
3. Improve corenlp.sh script and fix the sentence splitting issue;
4. Fix brackets parsing problem.