fix: polyfill Buffer for browser compatibility (#112)

* Polyfill with "buffer" and "assert" for browser environments
* Instead of relying on webpack to make this library browser compatible, we now use a buffer library that provides a polyfill when used in the browser

packages/ripple-binary-codec/src/serdes/binary-parser.ts

@@ -1,6 +1,7 @@
 import * as assert from "assert";
 import { Field, FieldInstance } from "../enums";
 import { SerializedType } from "../types/serialized-type";
+import { Buffer } from "buffer/";
 
 /**
  * BinaryParser is used to compute fields and values from a HexString