[relay] Feature/relay integration (#2244)

This update adds new relay integration for NetBird clients. The new relay is based on web sockets and listens on a single port.

- Adds new relay implementation with websocket with single port relaying mechanism
- refactor peer connection logic, allowing upgrade and downgrade from/to P2P connection
- peer connections are faster since it connects first to relay and then upgrades to P2P
- maintains compatibility with old clients by not using the new relay
- updates infrastructure scripts with new relay service

client/testdata/management.json

@@ -20,6 +20,13 @@
     "Secret": "c29tZV9wYXNzd29yZA==",
     "TimeBasedCredentials": true
   },
+  "Relay": {
+    "Addresses": [
+      "localhost:0"
+    ],
+    "CredentialsTTL": "1h",
+    "Secret": "b29tZV9wYXNzd29yZA=="
+  },
   "Signal": {
     "Proto": "http",
     "URI": "signal.wiretrustee.com:10000",
@@ -34,4 +41,4 @@
     "AuthAudience": "<PASTE YOUR AUTH0 AUDIENCE HERE>",
     "AuthKeysLocation": "<PASTE YOUR AUTH0 PUBLIC JWT KEYS LOCATION HERE>"
   }
-}
+}