Add hook to add explanations of hotkey actions via plugins.

classes/pluginhost.php

@@ -27,6 +27,7 @@ class PluginHost {
 	const HOOK_TOOLBAR_BUTTON = 15;
 	const HOOK_ACTION_ITEM = 16;
 	const HOOK_HEADLINE_TOOLBAR_BUTTON = 17;
+	const HOOK_HOTKEY_INFO = 18;
 
 	const KIND_ALL = 1;
 	const KIND_SYSTEM = 2;

include/functions.php

@@ -1934,6 +1934,11 @@
 				"help_dialog" => __("Show help dialog"))
 			);
 
+		global $pluginhost;
+		foreach ($pluginhost->get_hooks($pluginhost::HOOK_HOTKEY_INFO) as $plugin) {
+			$hotkeys = $plugin->hook_hotkey_info($hotkeys);
+		}
+
 		return $hotkeys;
 	}