... not assuming that it is invoked from cmake-proxies/CMakeLists.txt
This will allow modules to use lib-src libraries, and even for a module to be
the sole user of one of them.
So addlib lines may be moved out of cmake-proxies/CMakeLists.txt, when no
longer needed to build the reduced executable without the modules.
... So mod-foo defines FOO_API properly on the command line, for use in its
public header files; on Windows, appropriately expanding one way when compiling
the library, another way when compiling other code that uses it, so that all
will link correctly.
And added a python version that will be used on all platforms
when a suitable msgfmt isn't installed. (As long as python
is installed.)
Extracted all the Audacity specific functions from main cmake
list and moved them to their own module.
Rearrange the main cmake module a bit and misc. cleanup.
