Improve inSensorShadow

Use point in world coordinates as arguement in order to avoid unnecessary
transformation.
Fixed tests on Mac
Removed @private enum doc
Convert the single-tile Earth image into tiled imagery.
Merge pull request #914 from AnalyticalGraphicsInc/macFixes

Mac test fixes for b18
Update CHANGES.md.
Tweak CHANGES.md.
Merge branch 'master' of https://github.com/AnalyticalGraphicsInc/cesium into sensorImprovements
Replace remaining usages of old single-tile image.
Remove unused parameters from getIntersectionColor.:
Merge pull request #915 from AnalyticalGraphicsInc/natural-earth-2

Convert the single-tile Earth image into tiled imagery.
GeoJSON support for EPSG CRS type.

Earlier draft versions of GeoJSON have an EPSG CRS type.
While the 1.0 specification has no such type, many applications still generate GeoJSON in this format.
Changes after review.
Fix typo.
Merge pull request #918 from AnalyticalGraphicsInc/geojson

GeoJSON support for EPSG CRS type.
Cleanup CHANGES before releasing b18.
Merge pull request #919 from fstoner/sensorImprovements

Sensor improvements
Fix Hello World in Firefox.

The Cesium container div had no styling.
Bump Cesium version to b18.
Merge remote-tracking branch 'origin/master' into gltf