Fix a couple uses of ".prototype = new"

We don't want the THREE.Loader constructor to be executed, we just want
to setup our prototype chain. Using new would execute the constructor
logic of THREE.Loader.
Set prototype.constructor for all derived classes

Fixes #5570
Merge pull request #5603 from elisee/fix-5570

Fix #5570: Set prototype.constructor for all derived classes
Updated builds.
THREE: Being nicer to people still using CanvasRenderer. Fixes #5548 and #5601.
THREE: Moved Projector fallback code.
Updated builds.
Warn user if we change their texture settings.

If the user set a wrapS or wrapT parameter we should warn him if his
texture is not power of two.  We should also warn him if his minFilter
is changing.
Merge pull request #5614 from BenediktS/WrapWarnIfNotPowerOfTwo

Warn user if we change their texture settings.
Code clean up.
Updated builds.
CombinedCamera: Fixed Orthographic fov. See #5558.
Merge remote-tracking branch 'upstream/dev' into splitRaycaster