Class MacAddressOptionHandler added and implemented.
Explaining comment added.
MAC address delimiter made more abstract.
Exception during runtime resolved:
After calling the parse()-method the underlying OneArgumentOptionHandler calls setter.addValue(value) where value is a byte[6]. This method does - with a detour over ArrayFieldSetter - something like

byte[] field = new byte[1];
mac[0] = value;

which causes an IllegalArgumentException.

I have modified my OptionHandler to take the (correct) bypass over setter.asFieldSetter().addValue(value) which solves the problem. Therefore MacAddressOptionHandler is not longer a OneArgumentOptionHandler.
Wrapper class removed.
Don't know what came over me to take a Byte[] for a byte[]...
Another OptionHandler for UUIDs (java.util.UUID) added.
doc improvement
trim off brackets around it
Merge branch 'pull-46'

Conflicts:
	args4j/src/org/kohsuke/args4j/spi/Messages_de.properties