[saga-rg] AlreadyExists

I'm new to the Saga list and have started to look over the java code and various docs. I'm wondering if the exception AlreadyExists might be eliminated from the SAGA spec, in favor of different behavior -- namely to do nothing in the case where AlreadyExists would normally be thrown. This should be reasonable for mkdir(), adding a context, etc. I believe this would be simpler and nicer for users. Cheers, Steve