Optionally construct Viewer with a specified DataSourceCollection.
Changed Scene.globe to scene.globe in b28 changelog
Merge remote-tracking branch 'origin/master' into constructWithDataSources

Conflicts:
	CHANGES.md
Merge pull request #1815 from AnalyticalGraphicsInc/constructWithDataSources

Optionally construct Viewer with a specified DataSourceCollection
Merge pull request #1820 from cmorse/master

Changed Scene.globe to scene.globe in b28 changelog
Minor doc tweak.
Tweak the font size of code elements in doc.  Fix #1813.
Merge pull request #1822 from AnalyticalGraphicsInc/issue1813

Tweak the font size of code elements in doc.  Fix #1813.
Merge master to animation-collection2