Spruce up the readme a bit

I think the readme could put more of batman.js's strengths out on display :) Here's the summary of my proposed changes:

__Remove:__

-  "regular JS" -- is that a reasonable possibility without CoffeeScript's `extend`?
-  "node.js toolchain" -- I just doubt `cake test` is the first concern of people scoping out batman.js!

__Add: __

- short descriptions of each point, with links where appropriate
- a jab at JS curly braces (is that too far?)
- links to other stuff

@pushrax & @angelini, how do these sit with you guys? is this ok with you?