Added support for Koa, Upgraded devDependencies

[dougwilson]

This compact seems so trivial why not just have a module on npm that will allow any expressjs middleware to run on Koa instead of trying to patch every single expressjs middleware?

[niftylettuce]

@dougwilson good pt - what do you think of https://github.com/kaelzhang/express-to-koa/blob/master/src/index.js or https://github.com/vkurchatkin/koa-connect/blob/master/index.js?

[dougwilson]

I can see what express-to-koa is trying to do with the response object, but it is likely to run into more edge cases than it's worth. koa-connect is pretty much exactly what I would have written myself as a bridge.

[niftylettuce]

awesome, will use koa-connect instead, I agree re: express-to-koa