Adding "Total" to usage summary

String "Total" added for grep-like purposes and visibility.
Output:
                          9.2 GiB       Total


Example purpose:
for i in `who | awk {'print $1'} | grep -v root | sort | uniq`; do echo $i | tr -d "\n"; ./ps_mem.py -p $(pgrep -u $i | paste -d, -s) | grep Total; done