Add getRecommendedShards and automatic shard count in ShardingManager (#796)

* draft stuff

fix docstring for Client#token

Reorganise resolver

make env better for shards, clean up docs

Fix Gus' log messages

7

meh just gateway/bot not v7 :(

final changes, ready for mergin!

build docs

make default totalShards 'auto', fix docs for totalShards type

clean up docs more

run docs

* make consistancy real

* Update and rename getRecommendedShards.js to GetRecommendedShards.js

* Update GetRecommendedShards.js

* Update index.js

* Update RESTMethods.js

* Update Shard.js

* Update GetRecommendedShards.js

* Update ShardingManager.js

* run docs

src/client/rest/RESTMethods.js

@@ -14,7 +14,7 @@ class RESTMethods {
     this.rest = restManager;
   }
 
-  loginToken(token) {
+  loginToken(token = this.rest.client.token) {
     token = token.replace('Bot ', '');
     return new Promise((resolve, reject) => {
       this.rest.client.manager.connectToWebSocket(token, resolve, reject);
@@ -49,6 +49,10 @@ class RESTMethods {
     });
   }
 
+  getBotGateway() {
+    return this.rest.makeRequest('get', Constants.Endpoints.botGateway, true);
+  }
+
   sendMessage(channel, content, { tts, nonce, disableEveryone, split } = {}, file = null) {
     return new Promise((resolve, reject) => {
       if (typeof content !== 'undefined') content = this.rest.client.resolver.resolveString(content);