Updates to cenorship RFC identification section

@josephlhall, after our email conversation (October?), I finally got some time to look at your RFC in more depth. In this pull request, I have updated the identification content to be more technically precise and added a few more references. This is just an initial pass though, and we could add a lot more to this section and the rest of the RFC.

If further edits would be useful to you, @feamster and I would be happy to take further passes over the rest of the RFC.

Also, sorry for the size of the pull request; git looks for differences in each line and when I use fill-paragraph in emacs, it marks all of the text as a change. 

Additionally, some of your references seem messed up. I don't know what the formatting rules are for RFC citations, but some of your references are reused in multiple places and in some cases, you create multiple references for the same paper/resource. 

Finally, I didn't modify the pagination, so that is probably completely wrong now.