gnat_ugn.texi: Generalize "finding memory problems" section into a "memory management issues"...

2004-10-26  Cyrille Comar    <comar@act-europe.fr>
	    Vasiliy Fofanov  <fofanov@act-europe.fr>
	    Vincent Celier   <celier@gnat.com>

	* gnat_ugn.texi: Generalize "finding memory problems" section into a
	"memory management issues" section and document some of the useful
	memory pools provided as part of the GNAT library.
	Remove "virtual" from declaration of A::method2 in
	the simple example of Ada/C++ mixed system.
	Library Projects may be virtually extended: their virtual extensions
	are not Library Projects.
	Added section on extending project hierarchies.

From-SVN: r89678