Merge branch 'master' of git://github.com/gwaldron/osgearth

Conflicts:
	src/osgEarthQt/MultiViewerWidget
	src/osgEarthQt/MultiViewerWidget.cpp
	tests/feature_geom.earth
Added option to set touch sensitivity
Typo in last commit
Type
Add to last commit
Fix for almost infinite loop in "Insert intermediate Corners " code
Speed up evaluation of instance uri expression
fix for models with different scalings creating new Instance nodes
Fix Gdal driver to use fast subsampling to create elevation layers.
FIX compilation problem on Windows. Change 'round' to 'osg::round'
CMake 3.0 fix
Merge pull request #523 from remoe/patch-11

CMake 3.0 fix
ShaderLOD: add the rangeuniform cull callback and shaderfactory support.
Merge branch 'master' of github.com:gwaldron/osgearth
MPGeometry: add PRE_RENDER as a check when rendering without color layers
GLES: disable automatic h/w compression on GLES; require user to specify since many drivers on PV/ETC don't support it and rather require manual compression
BuildGeometryFilter: fix copy/paste bug that prevents single-point Point geometries from being built
RangeUniformCullCallback: add debugging code
VirtualProgram: add accept callback to compare set
OgrUtils: formatting
DepthOffset: try a vertex-shader-only method that is compatible with the logarithmic depth buffer