CMake supports the notion of installation components. Right now we have some
custom code for supporting swift components. I think that for installation
purposes, it would be nice to use the CMake component system.
This should be a non-functional change. We should still only be generating
install rules for targets and files in components we want to install, and we
still use the install ninja target to install everything.
Based on the same concept of swift-api-dump, this python wrapper
provides framework authors a convenient way to generate baseline or
diagnose ABI/API breakages from an existing toolchain where it has
swift-api-digester installed.
cmake installation part will be added in a separate PR.
rdar://problem/29649661
