Update for gcc-4.7
Merge branch 'master' (gcc-4.7, commit 'c7dd24a') into gcc-4.6

Reverts:
	source/a-except.ads
	source/a-filico.adb
	source/a-filico.ads
	source/a-tagins.adb
	source/a-tagins.ads
	source/a-tags.adb
	source/a-tags.ads
	source/s-finimp.adb
	source/s-finimp.ads
	source/s-finroo.adb
	source/s-finroo.ads
	source/s-soflin.adb
	source/s-soflin.ads
	source/s-stalib.ads
	source/s-stopoo.ads
	source/s-taskin.ads
	source/s-unwind.adb
	source/s-unwind.ads
	source/s-unwrai.adb
	source/s-unwrai.ads
	source/strings/a-chacon.ads
	source/tasking/s-tasren.adb
	source/tasking/s-tassta.adb
	source/tasking/s-tassta.ads
	source/tasking/univ-apple-darwin/s-tasins.adb
	source/zcx/s-unrase.adb
	source/zcx/s-unwhan.adb
	source/zcx/s-unwhan.ads

Removes:
	demo/subpool.adb
	source/a-undesu.adb
	source/a-undesu.ads
	source/s-finmas.adb
	source/s-finmas.ads
	source/s-stposu.adb
	source/s-stposu.ads
Add Ada.Containers.Generic_Sort
Add Ada.Iterator_Interfaces
Merge branch 'master' (gcc-4.7, commit '1ee8f38') into gcc-4.6

Modifications:
	source/a-iteint.ads
Reformat
Reformat
Make iterator in Ada.Directories derived from Ada.Iterator_Interfaces
Merge branch 'master' (gcc-4.7, commit '02b605e') into gcc-4.6

Modifications:
	demo/directories.adb
	source/directories/univ-apple-darwin/a-direct.adb
	source/directories/univ-apple-darwin/a-direct.ads
Insert Implicit_Dereference
Merge branch 'master' (gcc-4.7, commit 'dc021e4') into gcc-4.6

Modifications:
	source/a-refere.ads
	source/a-refstr.ads
	source/a-rewist.ads
	source/a-rezstr.ads
Make iterator in Ada.Environment_Variables derived from Ada.Iterator_Interfaces
Merge branch 'master' (gcc-4.7, commit 'da85de9') into gcc-4.6

Modifications:
	modified:   demo/cmdline.adb
	modified:   source/univ-apple-darwin/a-envvar.ads
Reexamine some entities required by compiler
Merge branch 'master' (gcc-4.7, commit 'ff1ad1a') into gcc-4.6

Conflicts:
	source/a-except.ads
	source/a-tags.ads
	source/s-finroo.ads

Modifications:
	source/s-unwrai.ads
Arrange demo/*
Merge branch 'master' (gcc-4.7, commit 'c832ddb') into gcc-4.6

Conflicts:
	demo/cmdline.adb
	demo/subpool.adb
Merge branch gcc-4.6 (commit 'cf139c0') into gcc-4.5

Conflicts:
	demo/image.adb
Add Ada.Text_IO.Iterators, Ada.Containers.Forward_Iterators and remove Ada.Containers.Input_Iterators
Merge branch 'master' (gcc-4.7, commit 'ab1c91a') into gcc-4.6

Modifications:
	demo/input2forward.adb
	source/containers/a-cofoit.adb
	source/containers/a-cofoit.ads
	source/textio/a-teioit.adb
	source/textio/a-teioit.ads