scripted-diff: Use the C++11 keyword nullptr to denote the pointer literal instead of the macro NULL

-BEGIN VERIFY SCRIPT-
sed -i 's/\<NULL\>/nullptr/g' src/*.cpp src/*.h src/*/*.cpp src/*/*.h src/qt/*/*.cpp src/qt/*/*.h src/wallet/*/*.cpp src/wallet/*/*.h src/support/allocators/*.h
sed -i 's/Prefer nullptr, otherwise SAFECOOKIE./Prefer NULL, otherwise SAFECOOKIE./g' src/torcontrol.cpp
sed -i 's/tor: Using nullptr authentication/tor: Using NULL authentication/g' src/torcontrol.cpp
sed -i 's/METHODS=nullptr/METHODS=NULL/g' src/test/torcontrol_tests.cpp src/torcontrol.cpp
sed -i 's/nullptr certificates/NULL certificates/g' src/qt/paymentserver.cpp
sed -i 's/"nullptr"/"NULL"/g' src/torcontrol.cpp src/test/torcontrol_tests.cpp
-END VERIFY SCRIPT-

src/addrman.cpp

@@ -69,13 +69,13 @@ CAddrInfo* CAddrMan::Find(const CNetAddr& addr, int* pnId)
 {
     std::map<CNetAddr, int>::iterator it = mapAddr.find(addr);
     if (it == mapAddr.end())
-        return NULL;
+        return nullptr;
     if (pnId)
         *pnId = (*it).second;
     std::map<int, CAddrInfo>::iterator it2 = mapInfo.find((*it).second);
     if (it2 != mapInfo.end())
         return &(*it2).second;
-    return NULL;
+    return nullptr;
 }
 
 CAddrInfo* CAddrMan::Create(const CAddress& addr, const CNetAddr& addrSource, int* pnId)