Make the DEFINE_INIT_FUNC macro compiler-agnostic
Update subhook
Remove redundant compiler ID checks

The Toolchain-* files already set the CMAKE_COMPILER_IS_GNU??? variable,
so use them instead:

cmake -DCMAKE_TOOLCHAIN_FILE=file ...
Revert "Remove README.md"

This reverts commit e1a1a5b04c29021d1d7976c57bafaf75de6439e2.

Conflicts:
	lib/python/ply
Port forum topic text to markdown