Upgrade system and filesystem to conform system_category and generic_category interface to N3090, the current C++0x working paper, section 19.5, System error support.

Refactor API macros into a new header, boost/system/api_config.hpp.

Prohibit user definition of API macros. Rationale: ensure all translation units use same definitions, cut number of environments that need to be tested.

[SVN r62313]

test/initialization_test.cpp

@@ -24,5 +24,5 @@ struct foo
 
 int main( int, char ** )
 {
-       return 0;
+  return ::boost::report_errors();
 }