Setup manymethods

Created a new branch in which I made one method for each column; I think this is the easiest way to manage over the long-term (with the inevitability of new data sources coming in).  Some other changes included fixing the pdo class, it wasn't tested before.  What's left for the methods is to finish `getListingMakeModel($listing)` and then they're done.  Following that, we need to loop through the array and insert/update as necessary.  Should be pretty straight forward.