Bug fixes - check the face if has uv and normal
sprite geometry supports texture mapping
depth buffer written while the material is not transparent.
Demos with ground planes have consistent up

Give the demos with ground planes of some sort a consistent "up"
direction for the camera, instead of having rotation be able to change
this. Simple change: Trackball to OrbitControls.
Merge pull request #5156 from erich666/dev

Demos with ground planes have consistent up
Examples clean up.
Merge branch 'SoftwareRenderEnhance' of https://github.com/DaoshengMu/three.js into dev

Conflicts:
	examples/js/renderers/SoftwareRenderer.js
SoftwareRenderer: Simplified code.
SoftwareRenderer: Spaces to tabs.
Sprite: Added uvs.
Updated builds.
Sprite: Removed unneeded updateMatrix.
Editor: Avoid scale NaNs. See #4946.
Updated builds.
fix ColladaLoader- result.scene must be a Scene to be renderable
Merge pull request #5162 from drewp/dev

fix ColladaLoader- result.scene must be a Scene to be renderable
PnlTri.js Rev. 2.0: handles vertices and edges on other edges; faster & smaller too
Merge pull request #5170 from jahting/pnltrixmpl

PnlTri.js Rev. 2.0: now handles vertices and edges on other edges (co-linearity)
Mesh raycast() returning new Face3( a, b, c, normal ) instead of [ a, b, c ] array. See #5164.
BufferAttribute: Added copyAt() to simplify item copying. (Not sure about naming)