Fix for MessageFormat '{0}' which will print as raw {0}, not the resolve...

Fixes the bug that ...

Exception in thread "main" org.kohsuke.args4j.IllegalAnnotationError: Die Option {0} ist mehr als einmal verwendet
	at org.kohsuke.args4j.CmdLineParser.checkOptionNotInMap(CmdLineParser.java:203)
	at org.kohsuke.args4j.CmdLineParser.addOption(CmdLineParser.java:180)
	at org.kohsuke.args4j.ClassParser.parse(ClassParser.java:34)
	at org.kohsuke.args4j.CmdLineParser.<init>(CmdLineParser.java:118)
	at org.kohsuke.args4j.CmdLineParser.<init>(CmdLineParser.java:93)
	at org.oneandone.idev.johanna.JohannahServer.main(JohannahServer.java:170)