Finally make the stupid pre/post processors work

src/PDUProcessor/Postprocessor/Center/EchoPduProcessor.ts

@@ -1,11 +1,15 @@
 import Center from "../../../Center/Center";
 import {PDU} from "../../../CommonObjects";
+import SmppSession from "../../../SmppSession";
 import Postprocessor from "../Postprocessor";
 
 const smpp = require("smpp");
 
 export default class EchoPduProcessor extends Postprocessor {
-	serverSessionType: string = Center.name;
+	constructor(type: string) {
+		super(type);
+		console.log(this.serverSessionType);
+	}
 
 	processPdu(session: any, pdu: PDU, ...args: any[]): Promise<any> {
 		return new Promise<any>((resolve, reject) => {