bugfix-RND-462-create-the-same-memphis-instance-in-js-sdk (#256)

* add createMemphisInstance

* update readme

README.md

@@ -1066,3 +1066,9 @@ await consumer.destroy();
 ```js
 memphisConnection.isConnected();
 ```
+
+### Create memphis instance 
+
+```js
+const memphisInstance = createMemphisInstance()
+```

src/memphis.ts

@@ -873,7 +873,7 @@ class Memphis {
         partitions = createRes.partitions_update.partitions_list;
       }
       this.stationPartitions.set(internal_station, partitions);
-      
+
       const producer = new Producer(this, producerName, stationName, realName, partitions);
       await this._scemaUpdatesListener(stationName, createRes.schema_update);
       this.setCachedProducer(producer);
@@ -1007,7 +1007,7 @@ class Memphis {
         }
       }
       this.stationPartitions.set(internal_station, partitions);
-      
+
       // the least possible value for batchMaxTimeToWaitMs is 100
       batchMaxTimeToWaitMs = batchMaxTimeToWaitMs < 100 ? 100 : batchMaxTimeToWaitMs;
       const consumer = new Consumer(
@@ -1026,7 +1026,7 @@ class Memphis {
         partitions,
         consumerPartitionKey,
         consumerPartitionNumber
-        );
+      );
       await this._scemaUpdatesListener(stationName, createRes.schema_update);
       this.setCachedConsumer(consumer);
 
@@ -1428,6 +1428,10 @@ export class RoundRobinProducerConsumerGenerator {
   }
 }
 
+export const createMemphisInstance = () => {
+  return new Memphis();
+}
+
 @Injectable({})
 export class MemphisService extends Memphis { }