Optimize .env and .zopen-config processing

[IgorTodorovskiIBM]

Since the new zopen symlinks all binaries, libraries, and man pages under a common bin, lib, share location, we no longer need to set the PATH, LIBPATH and MANPATH environment variables. However, if someone downloads the tool manually, then we should still retain that logic. So the idea is that we would decouple the required environment variables away from the .env into a .appenv, which zopen-config would source. This would greatly speed up the .zopen-config processing.

If there's any environment variables that are used within the application process, they should use zopen_append_to_zoslib_env (as in the case of Git):

zopen_append_to_zoslib_env() {
cat <<EOF
GIT_TEMPLATE_DIR|set|PROJECT_ROOT/share/git-core/templates
GIT_EXEC_PATH|set|PROJECT_ROOT/libexec/git-core
GIT_SSL_CAINFO|set|PROJECT_ROOT/cacert.pem
EOF
}

But variables that are needed by other tools or processes should go into zopen_append_to_env (we might need to change the name) as in the case of autoconf:

zopen_append_to_env()
{
cat <<EOF
export autom4te_perllibdir=\${PWD}/share/autoconf
export AC_MACRODIR=\${PWD}/share/autoconf


#To set M4 variable path
if [ -z "${M4_HOME}"  ]; then
    echo "Ensure M4_HOME is set and re-source the .env"
else
    export M4="\$M4_HOME/bin/m4"
fi
EOF
}

This would require a new build of all tools that have zopen_append_to_env logic.

[DevonianTeuchter]

Looks good to me and should improve init times for zopen-config

[IgorTodorovskiIBM]

I'll hold off merging this until after the beta since we'll need to trigger builds for most tools to get this to work.