Revision 1715172

Improve logging code a bit, fixing some architecture issues with the help of
my VS2015 compiler's support via printf. Enable more help from gcc/clang.

* buckets/ssl_buckets.c
  (apps_ssl_info_callback): Use last argument.

* incoming.c
  (client_connected): Use %pp for pointers.

* outgoing.c
  (clean_conn,
   connect_connection,
   serf__open_connections,
   reset_connection,
   read_from_connection,
   serf_connection_create2,
   serf_connection_close): Use %pp for pointers.
  (serf_connection_set_async_responses): Set as bool.

* protocols/fcgi_protocol.c
  (fcgi_process): Add missing argument.

* pump.c
  (serf_pump__data_pending): Remove logging that doesn't make sense here.
  (no_more_writes,
   socket_writev,
   serf_pump__write): Log pointer via %pp. Use generic value.

* serf_private.h
  (includes): Add apr.h to ensure __attribute__ is defined.
  (serf__log_nopref,
   serf__log): Annotate with __attribute__.