Add Ogre shader cache folder

[hhyyrylainen]

This will speed up launching games after the first time. It would also be good to figure out a way to precompile the shaders for all platforms.

Ogre recommends for this purpose creating a scene that uses all the materials and loading that in order to generate all the needed shaders and then using the shader cache store them.

[hhyyrylainen]

The first step is to make the Data/Cache folder also contains Ogre resources and that folder should be put into a path like .config/GameName/Leviathan/Version/Cache