Update experiments.md

doc.zih.tu-dresden.de/docs/data_lifecycle/experiments.md

@@ -3,6 +3,7 @@
 This article provides recommendations for building and running experiments properly on the ZIH system.
 Thereby, such an experiment consists of the following parts (at least some of them):
 
+* _decide about storage/workspace: /scratch/, /lustre/ssd, /beegfs/global0 or /tmp_
 * Input data
 * Software 
 * source code and scripts