Fixes #2318

It requires OES_standard_derivatives extension and benefits a lot from having EXT_texture_filter_anisotropic extension (set high anisotropy for bump texture).

Added new LeePerry example and modified materials2 WebGL example to show this in action.

Still quite a few things not solved:

- why there are seams at LeePerry model? (I suspect mesh discontinuities? this method is supposed to have less seams problems than normal mapping :S)
- it will crash without color map due to missing UVs, need to solve better UV initialization / sharing of shader parameters between chunks
- didn't check impact on environment mapping yet
- maybe also Lambert could be extended
- it should be somehow possible to precompute derivative maps and use this instead of "dHdxy_fwd()" method

Not really sure what to do with UVs for remaining geometries - they are either quite arbitrary or anyways not working well so far.

Also did some housekeeping for more geometry examples.

This fixes also TextGeometry.

This fixes IcosahedronGeometry and OctahedronGeometry (IcosahedronGeometry does have messed up UVs at the seam though this was broken even before, in r49).

Also made object rotation frame-rate independent in geometries example.

I'm not sure though bold => black is enough to make distinctions. Maybe on Windows we should use native Consolas with real bold as suggested by @spite?

This was creating mess when URL contained "html" also elsewhere than just at the end.

This reverts commit da1d2a66.

Otherwise you get "Uncaught TypeError: Cannot call method 'getInverse' of undefined".