Expande the compiler to fully build and zip plugins linked to components. Added plugin_updates area. Fixed gh-454 to insure placeholders are build even if no local db placeholders are found. Fixed gh-453 to prevent count error with null return value.

admin/layouts/joomla_plugin/code_above.php

@@ -26,7 +26,8 @@ $fields_tab_layout = 'fields_' . $layout_path_array[1];
 
 // get the fields
 $fields = $displayData->get($fields_tab_layout) ?: array(
-	'system_name'
+	'system_name',
+	'plugin_version'
 );
 
 $hiddenFields = $displayData->get('hidden_fields') ?: array();