Major refactoring - separated out rendering logic
Better appearance. More controls.
More helpful dev enviromment - gulp dev
Separate renderer config from renderer content.

Means a component rendering several sequences should not need
to change renderers as often (although that is very cheap).

It does however tidy some things up in the sequence viewer, make control
flow more obvious, at the expense of exporting some complexity to the
renderers.
New refactored build