https://www.oreilly.com/conferences/sample_proposals.html#tech
http://blowmage.com/2013/01/24/writing-conf-proposals
http://www.sarahmei.com/blog/2014/04/07/what-your-conference-proposal-is-missing/
http://weareallaweso.me/for_speakers/how-to-write-a-compelling-proposal.html