OBJLoader: change to the regular expressions for vertices, normals, and uv mappings to allow uppercase 'E' in scientific notation of numbers

centroid was originally used by CanvasRenderer, now that it computes it as needed we don't need the bloat anymore.

@algrs ok, I think I managed to get it to work now. I’m keeping a vertices array to map indices per object.

Should bring the OBJ(MTL)Loader into compliance with #3762.

OBJ loaders did not correctly preserve vertex and face list ordering and were creating duplicate vertex entries, rather than letting faces share vertices.

Eventually I would like to kill OBJMTLLoader altogether though...

The loader now ignores groups. Need to take a second look and try to implement MeshFaceMaterial when multiple usemtl. Then apply to OBJMTLLoader.

Gotta love regular expressions :)

Not too happy about it, but at least it's starting to be consistent. It's more of a monitor though...

It happens on a project I'm working on, not sure still why. I guess this approach is safer.

* OBJLoader now parses line per line in the same way OBJMTLLoader does.
* No more reusing of the same vertices array.
* Both now create a Object3D when finding a "o" and a Mesh when finding a "g" (or "usemtl").
* I used to like the obj format.

Using classic "loader.load( url, callback )" API instead in OBJLoader, STLLoader, VTKLoader.

OBJMTLLoader is still having just the incorrect EventDispatcher API, but there the situation is more complicated.

Fixed jquery dependency in OBJMTLLoader. Fixed variable redeclaration in OBJLoader. Fixed unreachable code in GeometryExporter warnings.

This Closure compiling of JS files from the examples already starts to be useful ;)

I had the issue that some of my OBJ-files weren't loaded by the OBJLoader provided in the examples. Parsing the file crashed with this exception:

Uncaught TypeError: Cannot read property 'x' of undefined Three.js:13
THREE.Vector3.addSelf (Three.js:13)
THREE.Geometry.computeCentroids (Three.js:91)
THREE.OBJLoader.parse (OBJLoader.js:295)
xhr.onreadystatechange (OBJLoader.js:21)

I traced the error to the OBJLoader and my OBJ files. The obj files were exported by 3ds Max Wavefront OBJ Exporter and slightly differ in format:

Where the loader expected:
v 0.4500 1.5256 0.6595

they were:
v  0.4500 1.5256 0.6595

Note the extra space. This threw off the regular expressions, the vertices weren't parsed and the computeCentroid failed. This commit changes the regular impression to accomodate this variance.