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/test/util_tests.cpp

@@ -1,11 +1,12 @@
-#include <vector>
-#include <boost/test/unit_test.hpp>
-#include <boost/foreach.hpp>
-
-#include "main.h"
-#include "wallet.h"
 #include "util.h"
 
+#include "sync.h"
+
+#include <stdint.h>
+#include <vector>
+
+#include <boost/test/unit_test.hpp>
+
 using namespace std;
 
 BOOST_AUTO_TEST_SUITE(util_tests)
@@ -200,7 +201,7 @@ BOOST_AUTO_TEST_CASE(util_FormatMoney)
 
 BOOST_AUTO_TEST_CASE(util_ParseMoney)
 {
-    int64 ret = 0;
+    int64_t ret = 0;
     BOOST_CHECK(ParseMoney("0.0", ret));
     BOOST_CHECK_EQUAL(ret, 0);