Add property name translation for PLYLoader

The property names in PLY files are given as strings, some
implementations may use different names for common properties.
This commit adds a translation mechanism based on a map,
which is specified via the constructor.

Example with no translation:
  loader = new THREE.PLYLoader();

Example with translation:
  loader = new THREE.PLYLoader({
	  		diffuse_red: 'red',
			diffuse_green: 'green',
			diffuse_blue: 'blue'
		});
Reverted #5367.
Tube Geometry documentation completed
cleanup whitespace
Completed geometry doc todos
Explicit method to set the property name mapping

The property name mapping can now be set by calling
setPropertyNameMapping, instead via the constructor.

Example:
	loader = new THREE.PLYLoader();
	loader.setPropertyNameMapping({
		diffuse_red: 'red',
		diffuse_green: 'green',
		diffuse_blue: 'blue'
	});
Updated documentation and usage.
Merge branch 'master' of https://github.com/svenpilz/three.js into dev

Conflicts:
	examples/js/loaders/PLYLoader.js
Merge pull request #5413 from HMUDesign/dev

cleanup generated JSON
Merge pull request #5414 from TatumCreative/docs-geometry

Geometry docs
Allow DataTexture to be used as cube map.
Merge pull request #5418 from tstanev/autodesk/cube_data_texture4

Allow DataTexture to be used as cube map.
build.py: utf-8 backwards support. Fixes #5416.
WebGLRenderer: Minor code clean up.
Updated builds.
Added new 'world' methods
Editor: Removed uneeded flag.
Editor: Clean up Menubar.Edit.
Removed all remaining buffersNeedUpdate flags.
Updated builds.