Version 2.0.0-beta3

The changes in beta 3 from beta 2 include:

• The main library files were converted to ECMAScript's import/export convention. The rollup tool
  is used to help generate the h3du_min.js file.
• HTML documentation included in distribution.
• "Norm" methods in H3DU.Math were renamed to use "Normalize" instead.
• New convex.js in extras folder generates the convex hull of a set of points.
• New interp.js in extras folder provides a cubic Bézier interpolation function.
• New spline.js in extras folder generates piecewise interpolating curves.
• New demos added, including demos showing how to generate procedural content using shaders.
• Several methods in H3DU.GraphicsPath were reimplemented.
• H3DU.BezierCurve and H3DU.BezierSpline are deprecated.
• H3DU.CurveBuilder and H3DU.SurfaceBuilder classes were created; they replace now-deprecated
  H3DU.CurveEval and H3DU.SurfaceEval classes.
• H3DU.MeshBuffer contains many new methods; in exchange, many of the H3DU.Mesh
  methods reimplemented in H3DU.MeshBuffer are deprecated.
• H3DU.Mesh is considerably deemphasized in this version; that class should only be used
  for building meshes, not storing them.
• H3DU.Curve and H3DU.Surface were created; these classes represent parametric curves
  and surfaces and offer methods for querying information at a given point on the curve or surface.
  Made several class derive from either class, including H3DU.BSplineCurve, H3DU.BSplineSurface,
  and new class H3DU.PiecewiseCurve.
• H3DU.RenderPass3D renamed to H3DU.RenderPass.
• Deleted fromBasic and fromBasicTexture methods from H3DU.PbrMaterial.
• Added JOINTS and WEIGHTS constants to H3DU.Semantic.
• Preliminary support for occlusion maps.
• Default diffuse/albedo in Material and PbrMaterial is now (1,1,1,1).
• New H3DU.BufferAccessor class represents a single vertex buffer.
• Many methods outside H3DU.Mesh now return H3DU.MeshBuffer instead of H3DU.Mesh.
• Bug fixes.

Full Changelog: v1.5.0...v2.0.0-beta3