链接两个buffer，类似数组的concat操作。实际操作的是两个Uint8Array。

appendBuffer.js

/**
 * Appends two ArrayBuffers into a new one.
 * 
 * @param {ArrayBuffer} buffer1 The first buffer.
 * @param {ArrayBuffer} buffer2 The second buffer.
 */
function appendBuffer(buffer1, buffer2) {
	var tmp = new Uint8Array(buffer1.byteLength + buffer2.byteLength);
	tmp.set( new Uint8Array(buffer1), 0);
	tmp.set( new Uint8Array(buffer2), buffer1.byteLength);
	return tmp;
}

example.js

// 创建一个新的全局对象，保存buffer
var buffer = new Uint8Array();
// 将新的buffer插入到之前的buffer上
buffer = appendBuffer(buffer,newbuf);