This commit contains several changes:

* print() is now treated as standard function
 * get rid of echo() function
 * fix test suite
and it fixes #26.

tests/utf8_variables.aer

@@ -9,7 +9,7 @@ class Main {
 	}
 
 	private function ダウンロード(){
-		echo $this->概要 . "\n";
+		print($this->概要 . "\n");
 	}
 
 	private function isUTF8($str) {