Adding shader class, extending containers to handle OSL related classes, fixed assembly's on_frame_begin.
Merge branch 'master' into OSL_merge
Fixed many PR comments, simplified param parsing from XML files.
Refactor param parse code, add projectfilereader support for osl classes.
Improved tests, formatting fixes and bug fixes.
Don't terminate the app in case of OSL param parsing errors.
Fixed more PR comments.
Merge pull request #301 from est77/OSL_merge

OSL merge 8