remove trailing slashes in title

docs/README.md

@@ -1,11 +1,11 @@
 #### User-contributed documentation and links to third party docs
 
-`configuration/`
+`configuration`
 - improve power management: https://github.com/taradiddles/qubes-os/tree/master/powermgnt
 - use Qubes OS as a server: https://github.com/Rudd-O/qubes-network-server
 
-`hardware/`
+`hardware`
 - [Tips on choosing the right hardware](hardware/hardware-selection.md)
 
-`misc/`
+`misc`
 - Qubes cheat sheet (3.2) : https://github.com/Jeeppler/qubes-cheatsheet