remove testcode in pformat.c, consolidate configure namespace option experimental features

git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6078 4407c894-4637-0410-b4f5-ada5f102cad1
Make it possible to disable new enhancements

git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6079 4407c894-4637-0410-b4f5-ada5f102cad1
Explain new features

git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6080 4407c894-4637-0410-b4f5-ada5f102cad1
Add no as an option to experimental

git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6081 4407c894-4637-0410-b4f5-ada5f102cad1
Add async_uuid feature to local repository.  Patch also sent to Wine's ML.


git-svn-id: https://svn.code.sf.net/p/mingw-w64/code@6082 4407c894-4637-0410-b4f5-ada5f102cad1