* [ Material ]: Update SPDX License Identifiers
* [ Material ]: Correct Test Material License
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Co-authored-by: Max Wilfinger <6246609+maxwxyz@users.noreply.github.com>
"Professional CMake" book suggest the following:
"Targets should build successfully with or without compiler support for precompiled headers. It
should be considered an optimization, not a requirement. In particular, do not explicitly include a
precompile header (e.g. stdafx.h) in the source code, let CMake force-include an automatically
generated precompile header on the compiler command line instead. This is more portable across
the major compilers and is likely to be easier to maintain. It will also avoid warnings being
generated from certain code checking tools like iwyu (include what you use)."
Therefore, removed the "#include <PreCompiled.h>" from sources, also
there is no need for the "#ifdef _PreComp_" anymore
* Materials: Model Manager External Interface
Implement the ModelManagerExternal class for the external Materials
interface.
This is part of the ongoing merges of code to support external material
interfaces. In this PR the ModelManagerExternal class is implemented,
along with changes to supporting classes required for this class.
* Apply reviewer feedback
