Add C++11 header <cuchar>.

Add C++11 header <cuchar>.

2015-09-04  Edward Smith-Rowland  <3dw4rd@verizon.net>
	    Jonathan Wakely  <jwakely@redhat.com>

	* acinclude.m4 (GLIBCXX_CHECK_UCHAR_H): Define.
	* config.h.in: Regenerate.
	* configure: Regenerate.
	* configure.ac: Check for <uchar.h>.
	* include/Makefile.am: Add new headers.
	* include/Makefile.in: Regenerate.
	* include/c/cuchar: New.
	* include/c_compatibility/uchar.h: New.
	* include/c_global/cuchar: New.
	* include/c_std/cuchar: New.
	* include/precompiled/stdc++.h: Include <cuchar>.
	* testsuite/17_intro/headers/c++200x/stdc++.cc: Include <uchar.h>.
	* testsuite/17_intro/headers/c++200x/stdc++_multiple_inclusion.cc:
	Include <uchar.h>.

Co-Authored-By: Jonathan Wakely <jwakely@redhat.com>
From-SVN: r227488