Add JSON/MD documentation of protocol smart contracts

[jasonklein]

This adds basic JSON and MD of protocol contracts, generated using the solc --devdoc option. The natspec documentation that was used to generate these docs is not included in this PR, because while much of our documentation is formatted for readability, manipulations/massaging was required to make the natspec documentation readable in JSON/MD, in addition to other adjustments. So, the in-line documentation will need to be updated in a separate issue (along with the addition of the scripts used to produce these files).

Note: devdoc gives the parameters back in alphabetical order, not the order in which they appear in the signature, so for now it was more sensible to write the order out as part of the detail of each function rather than to display the params object as is provided by devdoc.

[benjaminbollen]

LGTM