Add etf encoding support with erlpack (#943)

* the performance from this is astounding

* help uws

* save 15 bytes in webpacks

* update readme

* why is markdown like this

* optimizations

* Update WebSocketManager.js

package.json

@@ -37,6 +37,7 @@
     "ws": "^1.1.1"
   },
   "peerDependencies": {
+    "erlpack": "github:hammerandchisel/erlpack",
     "node-opus": "^0.2.0",
     "opusscript": "^0.0.1",
     "uws": "^0.11.1"
@@ -58,6 +59,7 @@
   "browser": {
     "ws": false,
     "uws": false,
+    "erlpack": false,
     "opusscript": false,
     "node-opus": false,
     "tweet-nacl": false,