fixed compilation on Windows.
minor cleanups.
minor cleanups.
Comment code not ready yet in DisneyMaterial
Simplified OIIO's texture cache related code. Use a shared cache.
Fixed bug in last commit.
Fixed missing #ifdef OSL.
Merge pull request #474 from est77/est_shared_oiio_texcache

Simplified OIIO texture cache related code
Fixed metadata in disneymaterial

The metadata of DisneyMaterialLayer is the same with the one of
disneybdrf so the get_input_metadata of the later class has
been used as refactoring.

Also during the previous PR some metadata from DisneyMaterialFactory
was removed, because I thought it was not needed.

Signed-off-by: Marius Avram <marius.avram1309@gmail.com>
Merge pull request #476 from marius-avram/disneymaterial_metadata2

Fixed metadata in disneymaterial