Remove duplicate words from Lorem provider

The docs say:
> Each call to method faker.name() yealds a different (random) result. This is because faker uses __getattr__ magic, and forwards faker.Genarator.method_name()' calls tofaker.Generator.format(method_name)`.

So I assumed that by "different" it meant the words provider would yield unique results, and just wasted a bunch of time trying to debug my code when I kept hitting duplicate key constraints in my database. 

Updated the words list to be de-duplicated and sorted.