Break dependency of init on wallet.

This required some code movement (what was CWalletTx::AcceptToMemoryPool
doing in main?), and adding a few explicit includes that used to be
implicit through init.h.

src/wallet.cpp

@@ -777,6 +777,25 @@ void CWalletTx::AddSupportingTransactions()
     reverse(vtxPrev.begin(), vtxPrev.end());
 }
 
+bool CWalletTx::AcceptWalletTransaction()
+{
+    {
+        LOCK(mempool.cs);
+        // Add previous supporting transactions first
+        BOOST_FOREACH(CMerkleTx& tx, vtxPrev)
+        {
+            if (!tx.IsCoinBase())
+            {
+                uint256 hash = tx.GetHash();
+                if (!mempool.exists(hash) && pcoinsTip->HaveCoins(hash))
+                    tx.AcceptToMemoryPool(false);
+            }
+        }
+        return AcceptToMemoryPool(false);
+    }
+    return false;
+}
+
 bool CWalletTx::WriteToDisk()
 {
     return CWalletDB(pwallet->strWalletFile).WriteTx(GetHash(), *this);