Three.js, semver, and addons

[makc3d]

@marquizzo

“Why is GLTFLoader 2.4.3 not working with THREE r152?”

@The examples/js directory will be removed with r148

if you have mis-matching packages, say three 150 and addons targets 140.x, then running npm install will fail, the CLI will notify you about matching ranges, it’s rather hard to mess up in practice.