Second draft of code of conduct.

Based on feedback from https://github.com/NodeDC/CodeOfConduct/pull/1:
- http://speakup.io/coc.html
- https://www.djangoproject.com/conduct/
- http://geekfeminism.wikia.com/wiki/Conference_anti-harassment/Policy
Add contact information for Matthew and Josh.
Add Dan’s contact info, paragraph on presentations
Merge pull request #2 from adunkman/master

Update Code of Conduct.