Fix Gdal driver to use fast subsampling to create elevation layers.
FIX compilation problem on Windows. Change 'round' to 'osg::round'
FeatureSourceOGR: minor locking/cleanup fixes
BoundaryGen: increase the output precision to 12.
BoundaryGen: made the default precision 14 and added a --precision CLA
Consolidated TerrainProfile methods.
docs update
Docs updates
Merge branch 'master' of https://github.com/gwaldron/osgearth
Change fseek ftell method for file size to fstat.
Implement more accurate buffer calculations for subsampled gdal tiles.
Add comments to last code change.
Merge pull request #530 from rolandhill/fix-fseek

Change fseek ftell method for file size to fstat.
Update utilities.rst
ModelLayer: embed a mask layer inside a model layer so you can stitch in a terrain inset a bit easier
Merge branch 'master' of github.com:gwaldron/osgearth
Merge pull request #531 from rooi/master

Added heightmap to triton ocean
Added new MP profiling level (2) for running tile load averages; added a define for an engine-level tile node cache (possible alternative to pagedlod cache)
Merge branch 'master' of github.com:gwaldron/osgearth
SimpleSkyNode: traversal fix