Some small tweaks

Author: ocaisa

docs/eessi-usage.md

@@ -96,7 +96,7 @@ cd eessi-demo
 
 The contents of the directory should be something like this:
 
-``` { .bash .no-copy }
+``` { .output .no-copy }
 $ ls -l
 drwxr-xr-x 2 example users  4096 May  5 15:13 Bioconductor
 drwxr-xr-x 2 example users  4096 May  5 15:13 ESPResSo

docs/eessi-use-cases.md

@@ -10,6 +10,8 @@ EESSI enables a variety of use cases, including:
 
 These use cases are discussed in details in our open-access paper, available via <https://doi.org/10.1002/spe.3075>.
 
+## What will we cover in the rest of this tutorial
+
 In the rest of this tutorial we will explore aspects of these use cases:
 
 * Using EESSI as base layer for software, and installing additional software on top of EESSI using `EESSI-extend`