gnuplot diagrams are not rendered about panda HOT 2 CLOSED

```{render="gnuplot -e 'set terminal svg' -e 'set output \"%o.svg\"' -c %i"
     img="../../src/images/panda_gnuplot_example"
     out="/home/lontivero/Documents/Wiki/src/images" }
set xrange [-pi:pi]
set yrange [-1.5:1.5]
plot sin(x) lw 4, cos(x) lw 4
```

```{render="{{gnuplot}}"
     img="../../src/images/panda_gnuplot_example"
     out="/home/lontivero/Documents/Wiki/src/images" }
set xrange [-pi:pi]
set yrange [-1.5:1.5]
plot sin(x) lw 4, cos(x) lw 4
```