Objective C features manual

[Joseph S. Myers]

On Wed, 9 May 2001, Joe Buck wrote:

> Yes, doc updates are unlikely to cause regressions.  Though it would be
> nice to make sure not to document things in the branch that are only
> checked into the mainline. :-)

That's why I didn't simply copy the mainline objc.texi to the branch - 
since I don't know whether @compatibility_alias is a feature present and 
working on the branch.  If it is, the docs may as well be merged.

-- 
Joseph S. Myers
jsm28@cam.ac.uk