Hide key template instances behind factory functions.

And provide a separate "module library"
Update testing scripts.

module/regex_cfind.cpp

@@ -0,0 +1,11 @@
+
+module boost.regex;
+
+namespace boost::re_detail_600 {
+
+   bool factory_find(perl_matcher<const char*, match_results<const char*>::allocator_type, regex::traits_type>& m)
+   {
+      return m.find();
+   }
+
+}