Something the log4j ConsoleAppender does makes the console work correctly
on Windows. After trying to pull pieces of it out and run them manually
I decided to just put the appender back. We now once again start with the
ConsoleAppender then remove it immediately after starting.
Some features added in 1.4.2 use the difficulty value as an index to an
array so while before having it set to an invalid value would do nothing
or maybe cause an odd side effect somewhere it now crashes the server. This
patch ensures difficulty values are clamped between 0 and 3, inclusive.
