a-ngrear.adb (Solve): Make generic and move to System.Generic_Array_Operations.

a-ngrear.adb (Solve): Make generic and move to System.Generic_Array_Operations.

2011-10-13  Geert Bosch  <bosch@adacore.com>

	* a-ngrear.adb (Solve): Make generic and move to
	System.Generic_Array_Operations.
	* s-gearop.ads (Matrix_Vector_Solution, Matrix_Matrix_Solution):
	New generic solvers to	compute a vector resp. matrix Y such
	that A * Y = X, approximately.
	* s-gearop.adb (Matrix_Vector_Solution, Matrix_Matrix_Solution):
	Implement using Forward_Eliminate and Back_Substitute
	* a-ngcoar.adb: Reimplement in pure Ada to remove dependencies
	on BLAS and LAPACK.
	* a-ngcoar.ads ("abs"): Fix return type to be real.

From-SVN: r179912