docs: add restart notices after Retinue install or update

- Add an *Important* note after the Installation verification step stating
  that Hermes must be restarted for the newly installed plugin to load.
- Add the same note after the Updating verification step so users know
  a running Hermes session continues using the old Retinue version until
  restart.

diff --git a/doc/index.org b/doc/index.org
index d4ad6fa..7177061 100644 (file)
--- a/doc/index.org
+++ b/doc/index.org
@@ -67,6 +67,10 @@ Verify the plugin is active:
 hermes memory status
 #+end_src
 
+*Important:* If Hermes is already running, restart it. Hermes loads plugins
+at startup, so an active session will not see the newly installed Retinue plugin
+until it is restarted.
+
 * Updating
 :PROPERTIES:
 :CUSTOM_ID: updating
@@ -91,6 +95,10 @@ To verify the update after re-running the installer:
 hermes memory status
 #+end_src
 
+*Important:* Restart any running Hermes sessions. Hermes loads plugins at
+startup, so a running session will continue to use the previous version of
+Retinue until it is restarted.
+
 * Quick start
 :PROPERTIES:
 :CUSTOM_ID: quick-start