Merge: lib: Introduce Stanford CoreNLP wrapper

## Stanford Core NLP

Stanford CoreNLP provides a set of natural language analysis tools which can take
raw text input and give the base forms of words, their parts of speech, whether
they are names of companies, people, etc., normalize dates, times, and numeric
quantities, and mark up the structure of sentences in terms of phrases and word
dependencies, indicate which noun phrases refer to the same entities, indicate
sentiment, etc.

This wrapper needs the Stanford CoreNLP jars that run on Java 1.8+.

See http://nlp.stanford.edu/software/corenlp.shtml.

## Usage

~~~nit
var proc = new NLPProcessor("path/to/StanfordCoreNLP/jars")

var doc = proc.process("String to analyze")

for sentence in doc.sentences do
	for token in sentence.tokens do
		print "{token.lemma}: {token.pos}"
	end
end
~~~

Pull-Request: #1754
Reviewed-by: Jean Privat <jean@pryen.org>
Reviewed-by: Alexis Laferrière <alexis.laf@xymus.net>
Reviewed-by: Lucas Bajolet <r4pass@hotmail.com>