update mounts.sh to include free / total usage
before
```
$ dfcmd='df -T | awk "-F " '\''{n=NF; while (n>5 && ! ($n ~ "/")) n--; for (;n<NF;n++) printf "%s ", $n; print $n "\t" $2 }'\' ; eval "$dfcmd" ;
Available Use% Mounted on Type
/ ext4
/dev devtmpfs
```
after
```
$ dfcmd='df -T -m | awk "-F " '\''{n=NF; while (n>5 && ! ($n ~ "/")) n--; for (;n<NF;n++) printf "%s ", $n; printf "%s\t%5s/%5sM %8s", $n, $5, $3, $2; print "" }'\' ; eval "$dfcmd" ;
Available Use% Mounted on Available/1M-blocksM Type
/ 2637/ 9816M ext4
/dev 445/ 445M devtmpfs
```