File r38/lisp/csl/support-packages/README.m4 artifact e5ec9c3cf2 part of check-in 9992369dd3

m4-1.4.tar.gz is GNU m4, and is needed for automake and autoconf. If
none of these are pre-installed on your computer first unpack and build
m4, then autoconf, then automake. I go "./configure --prefix=$HOME" for
each and have $HOME/bin on my path.