Fix bounding sphere computation for polygons.
Add test.
Merge branch 'master' into polygon-bounding-sphere
Fix label documentation and example.
Fix tests.
Fix polygon outline bounding sphere computation.
Merge pull request #1625 from AnalyticalGraphicsInc/polygon-bounding-sphere

Polygon bounding sphere
Merge remote-tracking branch 'origin/master' into label-docs
Changes per review.
Merge pull request #1626 from AnalyticalGraphicsInc/label-docs

Fix label documentation and example.
Merge remote-tracking branch 'upstream/master'