* stabs.texinfo: Remove node Quick Reference and put its children

	* stabs.texinfo: Remove node Quick Reference and put its children
	directly under the main menu.

	* stabs.texinfo: Many more changes to bring it into line with
	AIX documentation and reality.  I think it now has all the
	information from the AIX documentation, except that I burned
	out when I got to variant records (Pascal and Modula-2) and
	all the COBOL types.  Oh well, we can add them later when we're
	worrying more about those languages.

	* stabs.texinfo (Automatic variables): Talk about what it means
	to omit the symbol descriptor.