Added better error handling to allow tessellation to succeed even when GEOS crop fails.
Merge branch 'master' of https://github.com/gwaldron/osgearth
ModelLayer: fix issue with double-locking a mutex on linux
Merge branch 'master' of github.com:gwaldron/osgearth
Fix: compile error in OSG >= 3.1.8
Merge branch 'master' into topic-splat
Splat: add an option to splat before or after image layers