Even more terrain gen tweaks

- Added an ore pass
- Tweaked the cave pass
- Lowered the target framerate from 60 to 30
Render Tweaks

- Fixed non-opaque blocks rendering faces against opaque blocks
- Added some logging to chunk generation, to get an idea of what is
sucking up time
More ores

- Added iron ore
- Added gold ore
- Added the pdn file to the solution to make editing easier