refactor: circuit relay to async (#477)

* refactor: add dialing over relay support

* chore: fix lint

* fix: dont clear listeners on close

* fix: if dial errors already have codes, just rethrow them

* fix: clear the registrar when libp2p stops

* fix: improve connection maintenance with circuit

* chore: correct feedback

* test: use chai as promised

* test(fix): reset multiaddrs on dial test

test/utils/base-options.browser.js

@@ -9,5 +9,13 @@ module.exports = {
     transport: [Transport],
     streamMuxer: [Muxer],
     connEncryption: [Crypto]
+  },
+  config: {
+    relay: {
+      enabled: true,
+      hop: {
+        enabled: false
+      }
+    }
   }
 }