Smarty v5 update test, initial code setup

src/Compile/Modifier/StringFormatModifierCompiler.php

@@ -0,0 +1,18 @@
+<?php
+namespace Smarty\Compile\Modifier;
+/**
+ * Smarty string_format modifier plugin
+ * Type:     modifier
+ * Name:     string_format
+ * Purpose:  format strings via sprintf
+ *
+ * @author Uwe Tews
+ */
+
+class StringFormatModifierCompiler extends Base {
+
+	public function compile($params, \Smarty\Compiler\Template $compiler) {
+		return 'sprintf(' . $params[ 1 ] . ',' . $params[ 0 ] . ')';
+	}
+
+}