Optimized texture filePath handling;
Added support to handle layered textures;
Fixed Texture paths;
Added new GP_INFO macro and some info statements;
Changed some loggings from warning to info (pure debug logs);
Merge branch 'refs/heads/LayeredTextures' into materialencoder

Conflicts:
	gameplay-encoder/src/Base.h
	gameplay-encoder/src/FBXSceneEncoder.cpp
Merge branch 'materialencoder' of https://github.com/Wikitude/GamePlay into materialencoder

Conflicts:
	gameplay-encoder/src/FBXSceneEncoder.cpp