Merge branch 'develop' into modules

Fixed Conflicts:
	include/boost/regex/config.hpp

Also fix up msvc build failures.
Example now build with msvc or with clang.  The build script is still hopelessly broken though.

test/module/regex_token_iterator_eg_2.cpp

@@ -17,6 +17,8 @@
   */
 
 
+import boost.regex;
+
 #ifdef __cpp_lib_modules
 import std;
 #elif defined(MSVC_EXPERIMENTAL_STD_MODULE)
@@ -27,8 +29,6 @@ import std.core;
 #include <iterator>
 #endif
 
-import boost.regex;
-
 boost::regex e("<\\s*A\\s+[^>]*href\\s*=\\s*\"([^\"]*)\"",
                boost::regex::normal | boost::regex::icase);