fix(core): Tightens the network stack (#479)

- [X] Removes network pause/resume
- [X] Adds back packet profiler
- [X] Adds state machine to keep track and trace netstates
- [X] Changes NetState.Running back to using an interlock exchange
- [X] Adds preliminary packet throttling support


### Packet Throttling
- `[GetThrottle <packetId>` to get the delay in milliseconds for that packet
- `[SetThrottle <packetId> <delay>` to set the delay in milliseconds for that packet
The settings are saved to `Configuration/throttles.json`

Projects/UOContent/Misc/DoorGenerator.cs

@@ -347,7 +347,7 @@ namespace Server
         {
             World.Broadcast(0x35, true, "Generating doors, please wait.");
 
-            NetState.Pause();
+            NetState.FlushAll();
 
             m_Map = Map.Trammel;
             m_Count = 0;
@@ -389,8 +389,6 @@ namespace Server
 
             var malasCount = m_Count;
 
-            NetState.Resume();
-
             World.Broadcast(
                 0x35,
                 true,