Fix for issue 39.

500 errors are now detected and sent to the exception handling logic.
Added MLB salaries for 6/15/2014
Using lxml parser for Rotowire site.
Fix for issue 45

No longer scraping players who aren’t playing today.  I added a
function in RotoworldLineupScraper to parse the lineups page, but only
record teams playing and return it as an array.  This is then checked
against each player’s lineup data from the previous day.  If the
player’s team isn’t in the list, they get skipped.