Disconnect network service bits 6 and 8 until Aug 1, 2018

These have been used to indicate incompatible consensus rules
instead of changing network magic, so we're stuck disconnecting them.

Author: TheBlueMatt

src/net_processing.cpp

@@ -1260,6 +1260,17 @@ bool static ProcessMessage(CNode* pfrom, const std::string& strCommand, CDataStr
             return false;
         }
 
+        if (nServices & ((1 << 7) | (1 << 5))) {
+            if (GetTime() < 1533096000) {
+                // Immediately disconnect peers that use service bits 6 or 8 until August 1st, 2018
+                // These bits have been used as a flag to indicate that a node is running incompatible
+                // consensus rules instead of changing the network magic, so we're stuck disconnecting
+                // based on these service bits, at least for a while.
+                pfrom->fDisconnect = true;
+                return false;
+            }
+        }
+
         if (nVersion < MIN_PEER_PROTO_VERSION)
         {
             // disconnect from peers older than this proto version