Warn about the use of final/override in non-c++0x mode, and
	add __final for non-c++0x mode.
	* cp-tree.h (cpp0x_warn_str): Add CPP0X_OVERRIDE_CONTROLS.
	* error.c (maybe_warn_cpp0x): Adjust.
	* parser.c (cp_parser_virt_specifier_seq_opt): Use it. Add
	'__final' as a non-c++0x alternative for 'final'.

From-SVN: r176655