How do you build the minified version?

[jwatte]

I noticed that Vector3 defines an "Up" static. I find this to be a bad idea in scene graphs, because there really is no reason to specify a fixed "Up" -- it's all relative to the camera (and gravity,) both of which should be configurable to fit whatever scene the developer happens to be using.
It's easy to fix the users of Vector3.Up -- cameras can default to Y but have a property for changing; billboarding should use the current camera; and geometry construction can be defined to slice spheres across the Y axis.
But, now that I've edited the .js files and the TypeScript files -- how do I build the version to include?
And how do I know whether I broke anything -- are there any unit tests?
Given that "zip" files are checked in for the tools, rather than the actual working directories, it doesn't feel like the actual development repository is what's here on GitHub?

[deltakosh]

Here is the "doc" for building minified version:
https://github.com/BabylonJS/Babylon.js/wiki/Creating-the-minified-version