Updated Intro based on Dr. Xie's structure, Minor changes on Evaluation

=> Discuss motivations of the problem
=> Discuss existing approaches to this problem and their limitations
(e.g., "keyword-based filtering or rule-based approach") [in the
current writing, you never explicitly talk about what these existing
approaches are like]
=> Discuss challenges faced by these existing approaches (here you
don't need to include those sentences in the end as in the current
writing "To address this challenge..."
=> Start with your paragraph with "To address these challenges along
with general challenges of applying NLP techniques on software related
artifacdts [21], we propose ICON: ...."
=> Elaborate the techniques in your approach. For those techniques that
address a specific challenge of the two challenges, state something
like "To address the first challenge, we propose ...." Note that you
should discuss other techniques in your approach besides those
techniques for addressing the two challenges.
=> Contribution list