Dinodex 20140925 rc

Updates based on PR feedback:
-DRYed Dinosaur's to_s() method
-used CSV's HeaderConverters and Converters to normalize data
-cleaned up Dinosaur's initialize method
-removed weight_classification property, created method on Dinosaur to check for "bigness"
--some notes on this: due to the way I'm filtering (with an `include?`) I wasn't able to get true/false checks working fully with the initial `big?` method I wrote. I ended up deciding to refactor the `big?` method instead of rewriting the `filter` method on Dinodex.
-the main.rb issue of returning all Carnivores when submitting Insectivores was a testing typo I left in by mistake, cleared this up with Juan during a quick code review/chat.