Add contributors and description to package.json

[RichardLitt]

Dearest humans,

You are missing some important community files. I am adding them here for you!

Here are some things you should do manually before merging this Pull Request:

• [x] Check that nothing drastic happened in the package.json.
• [x] We've added " JavaScript toolkit for creating interactive real-time graphs" as the description in the package.json. We got this from the GitHub repo description.
• [x] Check the package.json keywords. We added these from your GitHub topics: "charts", "d3", "graph", "javascript", "rickshaw", "svg".
• [x] Check that the bugs field in the package.json is OK. It doesn't match what we'd expect, which would be https://github.com/shutterstock/rickshaw/issues
• [x] We expected the repository url in the package.json to be https://github.com/shutterstock/rickshaw, and it wasn't. Is this intentional?
• [x] If there are more contributors, add them to the Contributors field in the package.json.

Note: This pull request was automatically generated by https://github.com/mntnr/build-a-space. Found an issue? Let me know!

[coveralls]

Coverage remained the same at 62.874% when pulling f82c11ba42df2fd2b1209d3623f39478ac2df39e on docs/2017-11-29 into a5492fd55995bd00929de88680d6a429c36467c6 on master.