Some rambling about packet formatting.
Brainscales introduction.
Partial stab at the neurogrid section.
Added brief intro to preliminary work section.
Pre-neurogrid refresh mess.
Added neurogrid tree topology figure.
First stab at neurogrid writeup.
Initial blurb about SpiNNaker.
Added spinnaker hardware abstractions breakdown figure.
Added rack label.
Added photographs of each architecture.
Add figure explaining skew.