FindVCRedist: Add a find module to locate vcredist_(arch).exe
Currently, including InstallRequiredSystemLibraries automatically installs runtime dlls locally (when used with MSVC). However, the recommended way to install the VC dlls is to use vcredist. Helpfully, InstallRequiredSystemLibraries sets MSVC_REDIST_DIR so that VC-supplied vcredist can be easily found and used. However, when using vcredist for system installation of dlls, the locally installed dlls should no longer be used. It is quite difficult to get rid of them, though.
I propose a switch (a variable) which disables actual installation of these dlls, but still sets all the needed variables so that users can create their own install() rules, if needed.