README for prt-utils

Starting with version 1.3.2, the user-facing part of prtverify has
two alternative implementations: bash and gawk. The `make install` 
rule creates /usr/bin/prtverify pointing to the gawk version. 
Feel free to change the target of the symlink, define an alias 
in your profile (e.g., alias prtverify="/usr/bin/prtverify.sh "),
or put a different prtverify earlier in $PATH, if you prefer 
a more traditional wrapper for the awk tests.