Minor changes to overview

slides/overview.md

 ## Overview
 
 0. The Terminal
-1. What is `git`? Why do I need it? (5 min)
-2. GitHub and GitLab (5min)
-    * Practical session (5 min)
+1. What is `git`? Why do I need it? <!--(5 min)//-->
+2. GitHub and GitLab <!--(5min)//-->
+    * Practical session <!--(5 min)//-->
         - GitLab interface
         - GitHub interface
-3. The 5 essential commands (10 min)
-    * Practical session (15 min)
-        - init
-        - clone
-        - add
-4. Branches (10 min)
-    * Practical session (10 min)
-5. Forks (10 min)
-    * Practical session (10 min)
-6. Evaluation (10 min)
+3. The 5 essential commands <!--(10 min)//-->
+    * Practical session <!--(15 min)//-->
+        - `clone/pull` / `status` / `add` / `commit` / `push`
+4. Branches <!--(10 min)//-->
+    * Practical session <!--(10 min)//-->
+5. Forks <!--(10 min)//-->
+    * Practical session <!--(10 min)//-->
+6. Evaluation <!--(10 min)//-->