Updating README.md

[whichsteveyp]

I don't know why it caught my eye, but const isn't available in many scenarios without a transpiler.

[mjackson]

Absolutely agree. But import probably isn't available in those environments either. So we just need to decide to do one or the other.

[whichsteveyp]

Oh no, I know. import block says its for use with a transpiler, this section says it's for use without one, but uses const which you can't do ;)

[ryanflorence]

I kinda want to just say "all of our examples use ES2015, if you don't know what that is, please learn it."

[mjackson]

this section says it's for use without one

Ah, excellent point. I guess we should just use require in that section.

[mjackson]

Oh geez. It already does. /facepalm

[mjackson]

Thanks, @sprjr !