I think I'll be a little more comfortable merging this if there was also a test making sure that this did what it's supposed to do. Glyn, please feel free to merge and add the test later if you think this is a reasonable implementation.

Yes, please add a test case that should fail before the code fix and that succeeds after. You can put this test inside uri_test.cpp.

I added the test case and the fix with addition of typedef's in network::http::request_header/response_header because header concept requirements. Async http server can't be build without this fix.