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
Modify expression set in dinsey editor inputs

The color which should be found in the input of the disney material
editor must be transformed from sRGB to linear RGB.

Also the texture expression should be different. It should look like
texture("path", ...).

Signed-off-by: Marius Avram <marius.avram1309@gmail.com>
renamed ARCH32 and ARCH64 to APPLESEED_ARCH32 and APPLESEED_ARCH64.
Curve Rendering PR Commit - Basic Curve Loading - Curve Tree - Rendering with materials and shadows
Merge pull request #479 from sriravic/curve_upstream_PR

Curve Rendering PR Commit - Basic Curve Loading - Curve Tree - Rendering...
Merge branch 'master' of github.com:appleseedhq/appleseed
fixed comment and minor cosmetic tweaks.
added a comment.
minor code reordering.
Fixed some minor issues
Merge pull request #480 from sriravic/curve_upstream_PR

Fixed some minor issues
APPLESEED_ARCH32 and APPLESEED_ARCH64 are now defined in foundation/platform/arch.h.
minor formatting tweaks.
minor edit.
Merge branch 'master' of github.com:appleseedhq/appleseed
remove redundant definitions of APPLESEED_ARCH32 / APPLESEED_ARCH64.
Fixed gcc 4.7 compile error
many small fixes and cleanups around the new curves feature.
Merge branch 'master' of github.com:appleseedhq/appleseed

Conflicts:
	src/appleseed/renderer/modeling/object/curveobject.cpp