Recompute bounding shapes

[mrxz]

PR that addresses the underlying problem of aframevr/aframe#5311. Whenever the update method on the TextGeometry is called, the boundingBox and boundingSphere will now be recomputed (if present). This is the same logic that BufferGeometry and LineSegmentsGeometry use.

Note: this PR can't be automatically merged as I rebased it onto the latest master of the original repository (https://github.com/Jam3/three-bmfont-text). This included a couple of nice clean-ups, like the removal of the dependency on https://github.com/Jam3/three-buffer-vertex-data and the object-assign ponyfill. For easier reviewing, please see:

• The diff between this master and the rebased version: https://github.com/dmarcos/three-bmfont-text/compare/master..mrxz:three-bmfont-text:rebase
• The commit that introduces the new logic: eed4878

[dmarcos]

This doesn't seem to be mergable (conflicts)

[mrxz]

This doesn't seem to be mergable (conflicts)

It's rebased on upstream master, didn't want to misrepresent their changes. Easiest would be to pull it in as another branch, GitHub sadly doesn't allow a PR to target a new branch.

[dmarcos]

Are the commits in our fork still relevant? We can perhaps switch back to the original?

[mrxz]

Are the commits in our fork still relevant? We can perhaps switch back to the original?

Sadly we can't switch back to the original. While some changes in our fork are superseded, the biggest one converting to ES6 classes is still needed (Experience-Monks#41, Experience-Monks#46, Experience-Monks#49)

Not to mention the additional bug fix of recomputing the bounding shapes.