Added optional Three.js and jQuery scripts to main layout.

Toggleable by per-page YAML front matter:
---
jquery: true
threejs: true
---
Added a page with a basic Three.js canvas
Our sphere now moves, so we can tell it's animated.
Added a set of orbiting controls from the Three.js examples
Fiddling with the lights
Reorganized some of the code
A bit more reorganizing
Tweaked title
Our renderer now shows a heightmap type thing rather than a sphere.
Allow for arbitrary height function for our heightmap
Add some randomness to our debug maps
A bit of rearranging, moved scene into a global var.
Changed whitespace to 4 spaces per tab
On second thought, made scene not a global variable.
Formatting!
Our heightmap can now change at the click of a button.
Renamed heightmap to mapMesh for more accuracy
Added some functionality to load a heightmap from an image
Depth, not height!
Added in heightmap images