cosmetics.
Merge pull request #506 from est77/master

Added empty constructors to prevent gcc warning.
OSL trace call.
Fixed error in last commit.
reduced wire thickness in screen-space wireframe diagnostic surface shader.
Merge pull request #507 from est77/est_OSL_trace

OSL trace call
Fixed PR comments
Merge remote-tracking branch 'upstream/master' into est_OSL_trace
Merge pull request #508 from est77/est_OSL_trace

fixed OSL trace PR comments
refactoring.
fixed issues reported by Coverity.

the only meaningful ones are uninitialized ray depth and a memory leak.
Merge branch 'master' of github.com:appleseedhq/appleseed
addressed issues reported by Coverity.

all minor.
improved formatting.
properly handle wrapping in foundation::find_next_available_path() and added unit tests.
cosmetics.
cosmetics.
refactoring.
change Max Ray Intensity step from 0.5 to 0.1 in Render Settings dialog.
bug fix: max ray intensity wasn't applied for secondary rays hitting the environment in PTNE engine.