Flip CZML pixel offset origin for billboard and label.

Because CZML is not yet versioned, we can't distinguish new from old CZML.  So, until we implement all our breaking changes in CZML 1.0, keep the existing convention in CZML.
Properly handle flipping sampled pixel offset values.
Remove Fresnel, Reflection, and Refraction materials.
Update CHANGES.md
Merge pull request #1875 from AnalyticalGraphicsInc/remove-materials

Remove Fresnel, Reflection, and Refraction materials.
Update JSDoc to 3.3.0-alpha9
Fix documentation errors
Fix regression where modules were prefixed with "module:"
Update CHANGES.md
Merge pull request #1876 from AnalyticalGraphicsInc/upgradeJsDoc

Upgrade JSDoc
Merge pull request #1874 from AnalyticalGraphicsInc/flipCzmlPixelOffset

Flip CZML pixel offset origin for billboard and label.
Make sure CZML and GeoJSON errors propagate properly

Use `otherwise` instead of a second argument to when so that exceptions thrown by invalid CZML propagate properly.
Merge pull request #1877 from AnalyticalGraphicsInc/otherwise

Make sure CZML and GeoJSON errors propagate properly
Update version to b30