Explain commands under the first on the page (#158)

meldra · web-flow · commit 148872848b08 · 2021-09-02T16:37:31.000-04:00
diff --git a/content/_guides/registration.md b/content/_guides/registration.md
@@ -38,6 +38,9 @@ may have.
    /nick YourNick
    ```
 
+   Lines starting with the `/` symbol are commands, which you can type into
+   the chat field in the IRC client.
+
 3. **Register** your IRC nick:
 
    ```irc
