Add :writer attribute to delegate method

Hi Nathan,

Nice patch, but I don't think this would add anything that's really useful or missing right now. I'm curious about what the rest thinks, though. :)

-1

A big -1 from here too, sorry.

Doing:

delegate :name, :name=, :to => :client

is not only shorter, it's also more readable and concise.

I did it more for situations where one would like to delegate a handful of methods, but not have to explicitly write the writer methods out:

delegate :name, :phone_number, :street, :city, :to => :client, :writer => true

It was something that came in handy when for a large and complex API building project; we needed to keep data off a particular model acting as a tree, so we could version each node at their smaller size. It's a rather niche feature though, so I completely understand the -1's. One learns by trying though, right? =]

For all intents and purposes, :writer is only helpful when delegating multiple methods with writers.