Added module to scrap NBA Twitter handles

[nhatbui]

trafficstars

My contribution to this very cool package: I had needs to get the Twitter accounts off of basketball-reference.com and this package had a great foundation. The Twitter module simply scraps the page. I did not add any functionality to query it. I also included an example of what can be done.

[FranGoitia]

Thanks for your contribution. It is indeed useful and according to Nate Silver, professional gambler Haralabos Voulgaris, inputs data from players's Twitter to his ML models. I'll merge it once the indentation issues are solved.

[nhatbui]

Hi! I should have updated the indentation correctly. Thanks for pointing it out!