Added a page about job arrays

docs/g5k/getting-started-g5k.md

@@ -1,3 +1,5 @@
+[:fontawesome-solid-download: Presentation slides [pdf]](slides.pdf){: .md-button .md-button--link }
+
 # Introduction
 
 Grid'5000 is a large-scale and flexible testbed for experiment-driven research in all areas of computer science, with a focus on parallel and distributed computing, cloud, HPC, Big Data and AI.
@@ -738,7 +740,7 @@ While specifying a command of their own with their reservation, users can execut
 Here is a small bash script that will deploy an environment and run a stress command:
 
 ```bash
-#! /bin/bash
+#!/bin/bash
 
 # bash strict mode configuration
 set -euo pipefail