issue #446 apps usability - disable app if attached to a plugin that is uninstalled, allow system apps to be soft deleted and undeleted from the edit pane.

install/update.php

@@ -1,6 +1,6 @@
 <?php
 
-define( 'UPDATE_VERSION' , 1185 );
+define( 'UPDATE_VERSION' , 1186 );
 
 /**
  *
@@ -2472,3 +2472,12 @@ function update_r1184() {
 		return UPDATE_SUCCESS;
 	return UPDATE_FAILED;
 }
+
+function update_r1185() {
+
+	$r1 = q("alter table app add app_plugin char(255) not null default '' ");
+
+	if($r1)
+		return UPDATE_SUCCESS;
+	return UPDATE_FAILED;
+}