Added basic playground

Author: aure

Package.resolved

@@ -0,0 +1,18 @@
+//: Simple Playground to test if STKAudioKit is working 
+import AudioKit
+import STKAudioKit
+import Foundation
+
+let shaker = Shaker()
+
+let engine = AudioEngine()
+engine.output = shaker
+
+try! engine.start()
+
+while true {
+    let type = ShakerType(rawValue: (0...22).randomElement()!)!
+    print(type)
+    shaker.trigger(type: type)
+    sleep(1)
+}

Playgrounds/Hello World.playground/Contents.swift

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<playground version='5.0' target-platform='macos' display-mode='rendered' buildActiveScheme='true' executeOnSourceChanges='true' importAppTypes='true'>
+    <timeline fileName='timeline.xctimeline'/>
+</playground>