Add missing language versions.

js/rhino/toolsrc/org/mozilla/javascript/tools/resources/Messages.properties

@@ -130,7 +130,7 @@ msg.jsc.usage =\
 Usage: java {0} [OPTION]... SOURCE...\n\
 Valid options are: \n\
 \  -version VERSION   Use the specified language version.\n\
-\                       VERSION should be one of 100|110|120|130|140|150.\n\
+\                       VERSION should be one of 100|110|120|130|140|150|160|170.\n\
 \  -opt LEVEL         Use optimization with the specified level.\n\
 \                       LEVEL should be one of 0..9.\n\
 \  -debug, -g         Include debug information.\n\