* move is* properties to prototypes and remove unused ones

* rebuild

* merge dev -> less-is

* remove rebuild from PR

* convert to ES modules

* rebuild

* move shaders back into glsl files

* reinstate polyfills

Fixes #5570

BufferGeometry based THREE.AxisHelper

(Phewww!) I'm sure there are still things I missed...

Updated Closure compiler. Added more verbose compile warnings. Fixed all compile warnings. Started to fix runtime warnings in examples.

For verbose compile warnings to be practical I had to add externs and disable some warnings manually (there were tons of complains about "global this" and "cannot instantiate non-constructor"). Other solution would be to annotate explicitly constructors all over the code base.

(prompted by John Carmack's praise of static code analysis http://altdevblogaday.com/2011/12/24/static-code-analysis/)

* Camera is now a base object. PerspectiveCamera should be used instead. Figured out a way to show a warning when misused.
* OrthoCamera is now OrthographicCamera.
* Removed `target` from Camera.

Misc
* Renamed Trident to Axes.

Simplified `Trident`.
Added `setX`, `setY`, `setZ` methods to `Vector3`. They're handy for oneliners (see `CylinderGeometry`).

Added Trident to Geometry example. Found out that handling scene.objects from API wise is a bit confusing (childs are there too).

It can be added to the scene or as a child of any Object3D.
It is specially useful for debugging purpose.
The Trident name is borrowed from the Away3D project http://away3d.com/livedocs/3.6.0_lib/away3d/primitives/Trident.html