Implement Code of Conduct

[0xazure]

From the Town Hall:

• http://todogroup.org/opencodeofconduct/
• http://contributor-covenant.org/

Examples of CoCs:

• https://docs.puppetlabs.com/community/community_guidelines.html

Code of Conduct will be PR'd first to new-xkit/organization for evaluation and discussion, and then new-xkit/XKit once consensus is reached.

[0xazure]

May want to consider adapting the Node.JS Foundation's Community Contributing Guide. See also the write-up on healthy open source.