Fix ruby 1.9.3 compatibility and some refactorings

1.15.x was not working with ruby 1.9.3 anymore due to the added Hash call: 6b7eacdf49b7c7a063cab3dad7302596c4fde676
I've also refactored the load_lexicals and load_reviews methods and moved them to their own class.

BTW: your coveralls coverage is flawed, it seems to only check the spec files, maybe because the coveralls initialization is not on top of the spec_helper?

Martin