Request: Compatibility with Node 6

[jwu910]

Node 7 is currently required due to the use of async await functions.

Looking to add Node 6 and compatibility and maybe older versions in the future as well.

If this project is required to build before deployment, we may have to move that route which would require some reorganization.

[jwu910]

Should we include a polyfill, or should we remove the use of async and await? The latter would require we refactor the async functions to use Promise and callbacks.

[jwu910]

Fixed by #105