Change docs to use new performance test code,

upgrade docs to quickbook 1.7.

performance/config/posix.cpp

@@ -0,0 +1,15 @@
+///////////////////////////////////////////////////////////////
+//  Copyright 2015 John Maddock. Distributed under the Boost
+//  Software License, Version 1.0. (See accompanying file
+//  LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_
+//
+
+#include <regex.h>
+
+int main()
+{
+   regex_t pe;
+   int r = regcomp(&pe, "foo", REG_EXTENDED);
+   regfree(&pe);
+   return r;
+}