Default orientation for DataSource models

Eventually we plan on providing easy ways to specify orientation for Entity instances; but a small usability improvement in the short term is to just have the model stand up right if no orientation is provided.
Merge branch 'issue1940' into dataSource-model-defaults
Update default orientation after #1963
Merge remote-tracking branch 'origin/master' into dataSource-model-defaults
Merge remote-tracking branch 'origin/master' into dataSource-model-defaults

Conflicts:
	CHANGES.md
Merge pull request #1938 from AnalyticalGraphicsInc/dataSource-model-defaults

Default orientation for DataSource models