- fix compilation of netclient, netrec, netserver, piperead~, pipewrite~

- include mp3 externals from iem_mp3 and unauthorized and make mp3*.libs files

- put objects with conflicting names into a directory namespace

  		maxlib/scale
		Gem/scale
		iem/prepend
		cxc/prepend
		flext/prepend

- move .libs files to externals/build/src from externals/build/PLATFORM.  The
  platform-specific makefiles copy them before compiling.  If a
  platform-specific .libs file is needed, create it in the
  externals/build/PLATFORM directory.  The makefiles will use both:
  `test -f $*.libs && cat $*.libs` `test -f ../src/$*.libs && cat ../src/$*.libs`

- make MinGW makefile for "win" so that the GNU Makefile method will be
  standard on all platforms.

- do symlink aliases in externals/build/src/makefile.common

- write externals/build/doc/standardize-help.sh