Server Port Strategy Hotfix

For backwards compatibility, the engine was sometimes called using
an int for the server port directly. This would cause an error, so
casting to str() solves that without needing to change anything.

engine.py

@@ -222,10 +222,11 @@ class Engine():
         cmds = []
         for proto in ["tcp", "udp"]:
             # Need to change the match rule if multiple ports are specified
-            # Don't need to do any checking on the port since the iptables command can error, closing the engine
             # Default match policy is the protocol
             match_policy = proto
-            if any(x in self.server_port for x in [":", ","]):
+            # Don't need to do any checking on the port since the iptables command can error, closing the engine
+            # Change server port to str for backwards compatibility calling engine directly with an int
+            if any(x in str(self.server_port) for x in [":", ","]):
                 match_policy = "multiport"
 
             cmds += ["iptables -%s %s -p %s --match %s --%s %s -j NFQUEUE --queue-num %d" %