Added Code of Conduct
Updated spelling and clarified some language for readability
Shortened for clarity.
Update CODE_OF_CONDUCT.md

Change phrase "programming communities", add Zeeshan and myself as points of contact.
Update CODE_OF_CONDUCT.md

Generalizing code to github repo and meetup sites as well.
Update CODE_OF_CONDUCT.md

Including changes suggested by Ines.
Merge pull request #60 from papers-we-love/code-of-conduct

Added Code of Conduct