Update addon docs

Author: matthewjohns0n

docs/cli/built-in-commands/addons.md

@@ -10,7 +10,7 @@ Lists all add-ons available in the system.
 
     php eecli.php addons:list
 
-List add-ons that can be installed:
+List add-ons that are currently installed:
 
     php eecli.php addons:list i
 
@@ -26,7 +26,7 @@ or
 
     php eecli.php addons:list update-available
 
-List add-ons that can be uninstalled:
+List add-ons that can currently be uninstalled:
 
     php eecli.php addons:list u
 or