improved CameraHelper such that it does require to pass camera via .update(camera) if camera is already defined in the object's constructor

Set WebGLRenderer's default precision back to 'highp'. Added specifier to vertex shader too. Fixes #1602.

Anyways it wasn't working since we dropped multimaterials.

This white-on-white rendering wasn't really working.

Finally just reverted this particular terrain plane geometry to the old way, still don't know what's wrong with a new way :S.

Fixed all the examples that used PlaneGeometry except webgl_terrain_dynamic.html (not sure what's going on :S).

- removed not anymore existing ro.me specific remains (triggers, mesh colliders and shadow volumes)
- added custom properties for setting shadow map casting and receiving, depthWrite, depthTest, blending, doubleSided
- using Blender native "transparency" checkbox for setting out "transparent" property
- better handling of messed up texture slots

Yet again getting massive performance gains on nontrivial arrays (13 seconds => 0.3 seconds for 26K faces).

Splice is evil, since recently using it in Chrome leads to massive decrease in performance (messing with original array via splice is 10x slower than just creating new array from scratch and replacing the old array).