Better Docstrings/Comments on Contract Code

[villanuevawill]

As this code is likely to be audited by others more closely, I think it would be great to start building clear comments and docstrings. I really like the format here: https://github.com/ConsenSys/PLCRVoting/blob/master/contracts/PLCRVoting.sol#L78

I like how it's clearly split into its helpers, etc.. In this case, it could be split into bounty interfaces, fulfillment interfaces, and helpers/internal. It is very clean, makes for more readable content, and gives more trust to the standard.

[villanuevawill]

Also - have a line explaining it is a duplication check, explaining it is verifying no overflow, or explaining it is verifying we don't go over array max size.