Gatsby: Bypass react router path matching

[KyleAMathews]

I discovered recently that react-router can be very slow at matching routes https://github.com/reactjs/react-router/issues/3215

This will soon be (mostly) fixed but there'll still be 10-15 milliseconds spent matching the router (that's on a 2015 MBP so much much slower on an old android) that we should avoid.

We can load our own routing table into the browser and match path changes against that which will drop path matching times down to microseconds.

This will also probably make code splitting more convenient #10

[taion]

This will be cleaner with https://github.com/reactjs/react-router/issues/3262.

[taion]

As of React Router v2.2.0, getComponent now gets called with the router state, including params.

[KyleAMathews]

This is great! Thanks!

[KyleAMathews]

Closing as very old