Add DumpMempool and LoadMempool

src/init.cpp

@@ -207,6 +207,7 @@ void Shutdown()
 
     StopTorControl();
     UnregisterNodeSignals(GetNodeSignals());
+    DumpMempool();
 
     if (fFeeEstimatesInitialized)
     {
@@ -659,6 +660,8 @@ void ThreadImport(std::vector<boost::filesystem::path> vImportFiles)
         LogPrintf("Stopping after block import\n");
         StartShutdown();
     }
+
+    LoadMempool();
 }
 
 /** Sanity checks