Scrub

Let me know what you think! @mohit @jonahkagan 

(this is going to branch pr_onto because my first few commits went to master and so you wouldn't see the full PR. Once we merge this to pr_onto we can set it as master)
this is kind of a confusing line if the reader hasn't seen an example of what function_name, keywords, or object is yet. maybe add some examples to the introduction section above so the reader quickly knows how the usage looks?