Cleanup code using forward declarations.

Use misc methods of avoiding unnecesary header includes.
Replace int typedefs with int##_t from stdint.h.
Replace PRI64[xdu] with PRI[xdu]64 from inttypes.h.
Normalize QT_VERSION ifs where possible.
Resolve some indirect dependencies as direct ones.
Remove extern declarations from .cpp files.

src/compat.h

@@ -2,6 +2,7 @@
 // Copyright (c) 2009-2013 The Bitcoin developers
 // Distributed under the MIT/X11 software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
+
 #ifndef _BITCOIN_COMPAT_H
 #define _BITCOIN_COMPAT_H
 
@@ -18,17 +19,24 @@
 #undef FD_SETSIZE // prevent redefinition compiler warning
 #endif
 #define FD_SETSIZE 1024 // max number of fds in fd_set
-#include <winsock2.h>
+
+#include <winsock2.h>     // Must be included before mswsock.h and windows.h
+
+#include <mswsock.h>
+#include <windows.h>
 #include <ws2tcpip.h>
 #else
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <sys/fcntl.h>
 #include <arpa/inet.h>
-#include <netdb.h>
-#include <net/if.h>
-#include <netinet/in.h>
 #include <ifaddrs.h>
+#include <limits.h>
+#include <net/if.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <sys/fcntl.h>
+#include <sys/mman.h>
+#include <sys/socket.h>
+#include <sys/types.h>
+#include <unistd.h>
 #endif
 
 #ifdef WIN32