Merge #13235: Break circular dependency: init -> * -> init by extracting shutdown.h

1fabd59e7 Break circular dependency: init -> * -> init by extracting shutdown.h (Ben Woosley)
e62fdfeea Drop unused init.h includes (Ben Woosley)

Pull request description:

  Most includers just wanted to react to pending shutdown.

  This isolates access to `fRequestShutdown` and limits access to the shutdown api functions, including the new `CancelShutdown` for setting it to `false`.

Tree-SHA512: df42f75dfbba163576710e9a67cf1228531fd99d70a2f187bfba0bcc476d6749cf88180a97e66a81bb5b6c3c7f0917de7402d26039ba7b644cb7509b02f7e267

src/wallet/rpcwallet.cpp

@@ -1,5 +1,5 @@
 // Copyright (c) 2010 Satoshi Nakamoto
-// Copyright (c) 2009-2017 The Bitcoin Core developers
+// Copyright (c) 2009-2018 The Bitcoin Core developers
 // Distributed under the MIT software license, see the accompanying
 // file COPYING or http://www.opensource.org/licenses/mit-license.php.
 
@@ -20,6 +20,7 @@
 #include <rpc/server.h>
 #include <rpc/util.h>
 #include <script/sign.h>
+#include <shutdown.h>
 #include <timedata.h>
 #include <util.h>
 #include <utilmoneystr.h>
@@ -30,8 +31,6 @@
 #include <wallet/walletdb.h>
 #include <wallet/walletutil.h>
 
-#include <init.h>  // For StartShutdown
-
 #include <stdint.h>
 
 #include <univalue.h>