[dev] Proposal for Example Section in the docs: Complex example of Cust omer Postmaster Module

I have attached a Custom Postmaster module that implements ignoring messages and sending an email to the sender letting them know that the message was ignored and why. This might be a good thing to put in the doc examples as questions of this type have been asked before. I know there are procmail/spamassasin solutions to this kind of issue, but I don't have the luxury of either of those items. I have to work with our companies exchange server and thought this might be useful to those in a similar situation. Robert, Would you mind browsing the code and tell me if you think it looks efficient enough or whether I should change it. Regards, Tyler Hepworth