Merge remote branch 'upstream/master'
Merge branch 'master' of git://github.com/gwaldron/osgearth
Initial commit of tile index code.
Made sure the TileIndex driver's LRUcache was threadsafe.
Integrated custom intersector courtesy of user Robert Milharcic.
Merge branch 'master' of https://github.com/gwaldron/osgearth
Added missing PrimitiveIntersector files to CMakeLists.txt
Fix linux compiler warnings; partial work on normal interpolation in lod blending
Merge branch 'master' of github.com:gwaldron/osgearth
Rename osg_Normal; patch Controls with GLES header
osgearth_manip: add a toggle for viewpoint transition arcing (for testing)
Fixed some cache policy hint stuff; added 'resolution' property and docs to noise
Docs for noise driver
docs update
add ref_ptrs in tilenode and remove unused function
Started work on including occlusion culling in stylesheets.
Fixed scene clamping with annotations

The AnnotationLabelSource wasn't passing the full style, just the
TextSymbol.  Now it's passing in the full style including the
AltitudeSymbol so clamping is turned on.
applyStyle is now called in setMapNode on an AnnotationNode so clamping
can be setup if it needs to be.
Switched the OcclusionCullingCallback to use the
DPLineSegmentIntersector
Renamed style() to getStyle() in LabelNode so it will override the
correct virtual method.
Limiting the amount of time the OcclusionCullingCallback can run per frame.
Merge branch 'master' of https://github.com/gwaldron/osgearth
Fixed the problem with the new picker and line geometries.