Repo should also promote SCWC API

[kevincianfarini]

I noticed the CWC API is being pushed over using this repo as a mechanism for contacting members of the house. Turns out there's also a first party API for contacting senate members, as well.

https://www.senate.gov/senators/scwc.htm

This should be promoted in the README, because it takes a while to find that there's a Senate counterpart to the House API. It's not immediately obvious.

[chris-erickson]

It works great, but is not complete support yet. Also you need to go through the CWC Agent approval process. Just fine print for those who aren't familiar.