- C++ modules support [idea]

Notes on C++ Modules
====================

* Clang implements non-intrusive model via module maps, libc++ has one. But
  there is seem to work on TS implementation (-fmodule-ts).

* VC implements TS, has some tutorials.

* Seems like multi-file module export may be supported in the future. So the
  output becomes kind of like a library rather than a precompiled header file.

Questions
=========

* Is there/will there be support for modules in /showIncludes/-M*? We will
  need it for all the same reasons as for headers. In a sense, module is an
  always generated header.