Hyphen in Sentence Split & Hyphenated Words

Change 1:
A hyphen with spaces around it should be treated as sentence delimiters. However, a hyphen without space around it should be excluded in sentence delimiters. Otherwise, "high-performance", a hyphenated word, will be split incorrectly.

Change 2:
Added look ahead for hyphen in stop word regex. For example, there is a stop word "non" in "non-executive", and we should keep the "non" although it itself is a stop word, which means we should keep "non-executive" rather than "executive".