Rename DynamicScene to DataSources

Also renames lots associated objects for 1.0.  Everything is broken, will fix in next commit.
Fix code after DynamicScene rename.
Update CHANGES
Merge remote-tracking branch 'origin/master' into renameDynamicScene
Merge remote-tracking branch 'origin/master' into renameDynamicScene

Conflicts:
	CHANGES.md
Merge remote-tracking branch 'origin/master' into renameDynamicScene

Conflicts:
	CHANGES.md
	Source/DataSources/ReferenceProperty.js
Merge remote-tracking branch 'origin/master' into renameDynamicScene

Conflicts:
	CHANGES.md
Merge remote-tracking branch 'origin/master' into renameDynamicScene
Changes after review.
Use new terms in error message.
whitespace
Remove VectorGraphics and VectorVisualizer

See https://groups.google.com/forum/#!topic/cesium-dev/2FpDSXwDvVA
Fixed #1895
Use new terms (entity instead of object) in documentation.
Merge pull request #1883 from AnalyticalGraphicsInc/renameDynamicScene

Rename DynamicScene to DataSources
Merge remote-tracking branch 'origin/master' into removeVectors
Merge pull request #1896 from AnalyticalGraphicsInc/removeVectors

Remove VectorGraphics and VectorVisualizer
Fix minor typos

Find and replace in #1883 caused some bad pluralization.
Merge branch 'master' into polylineArc