Minor PrimitivePipeline cleanup.

`PrimitivePipeline.unpackCombineGeometryParameters` was not including the
cloned `modelMatrix` parameter as part of the result.  Because of this
`PrimitivePipeline.combineGeometry` was unecessarilly creating a dummy
object in order to clone it.  This is no longer needed.

There was also an uneeded clone of the resulting modelMatrix in Primtive.js,
the result matrix is the same instance that is passed into combineGeometry
so no clone is needed.

This change is basically a no-op but makes the code less confusing.
Fix HeightmapTessellator sample code.
Merge pull request #2099 from PatMahoney/master

Fix HeightmapTessellator sample code.
Matrix3 - Remove invalid sample code from doc.
Matrix4 - Fix sample code.
Merge pull request #2100 from PatMahoney/master

Matrix4 - Remove invalid sample code from doc.
Update README.md
Change version to 1.1

Also clan up CHANGES.
Merge pull request #2105 from AnalyticalGraphicsInc/versioning

Change version to 1.1
Using cosineAndsine to convert to WebMercator.
Tweak CHANGES.md
Merge pull request #2111 from fstoner/sineLatitude

Using cosineAndSine to convert to WebMercator.
Merge pull request #2097 from AnalyticalGraphicsInc/cleanup

Minor PrimitivePipeline cleanup.