Change detail namespace.

Big search and replace to change name of internal namepace so it's mangled with the Boost version number - the aim is to reduce the chances of mixing different header and library versions.

include/boost/regex/v4/protected_call.hpp

@@ -32,7 +32,7 @@
 #endif
 
 namespace boost{
-namespace re_detail{
+namespace BOOST_REGEX_DETAIL_NS{
 
 class BOOST_REGEX_DECL abstract_protected_call
 {