Merge branch 'master' into OSL_merge
Merge branch 'master' into OSL_merge
Merge branch 'master' into OSL_merge
Adding a ref to OSL's shading system in shading context.
Merge branch 'master' into OSL_merge
Some changes required to execute OSL shaders.
Formatting fixes.
Restored studio settings file.
Fixed PR comments.
implemented ray depth.
removed experimental surface shaders.
Merge pull request #297 from est77/OSL_merge

OSL merge 6
minor styling fixes.
added UNREACHABLE macro to inform (portably) the compiler that code is unreachable.
renamed some preprocessor symbols.
Changed FOUNDATION_ALIGN to APPLESEED_ALIGN
renamed rules-related elements in project file format.
added a specialization of foundation::from_string() taking a const char*.
tweaked comment.
fixed compilation of devkit sample.