adding yelp post
Update 2014-09-02-yelp-vegas.md

Added a link and just one sentence.
Update 2014-09-02-yelp-vegas.md

first round of edits. more coming
Update 2014-09-02-yelp-vegas.md

more edits
Tims post formatted
Tims post renamed
Merge pull request #65 from CartoDB/yelp

Tim's post