usage: /usr/bin/gencnval [-options] [convrtrs.txt]
	read convrtrs.txt and create icudt79l_cnvalias.icu
options:
	-h or -? or --help  this usage text
	-v or --verbose     prints out extra information about the alias table
	-q or --quiet       do not display warnings and progress
	-c or --copyright   include a copyright notice
	-d or --destdir     destination directory, followed by the path
	-s or --sourcedir   source directory, followed by the path