gnat_rm.texi: Document s-ststop.ads

2009-07-15  Robert Dewar  <dewar@adacore.com>

	* gnat_rm.texi: Document s-ststop.ads

	* impunit.ad: (Map_Array): New table of alternative names
	(Get_Kind_Of_Unit): Return possible suggested alternative name

	* impunit.ads (Get_Kind_Of_Unit): Return possible suggested
	alternative name.

	* sem_ch10.adb (Analalyze_With_Clause): Add name of possible
	alternative unit if an implementation unit is with'ed.

From-SVN: r149685