fixed errors for non-loaded texture
Only Cairo renderer set when begin pdf called, otherwise there is garbage in the pdf from the gl renderer
Merge branch 'master' of https://github.com/openframeworks/openFrameworks
fix for pdf rendering, and no gl renderer at the same time
Merge pull request #2844 from NickHardeman/master

Check for texture in the modelNoise example and only cairo renderer with begin save as pdf