Instead of having the systemd user units in .config/systemd/user/ who's
programs require access to a environment variable to define them
explicitly using "Environment = 'VAR=value'". Instead from .bashrc and
.zshrc we can import all environment variables using "systemctl --user
import-environment" or import variables individually like so "systemctl
--user import-environment VAR_NAME".
Here I import (using the method above) both $PATH and $SMLNJ_HOME so
that they can be used by emacs (and maybe some other
program/systemd-user-unit I have forgotten).
Signed-off-by: Collin J. Doering <rekahsoft@gmail.com>