Add playground with live view controller

This playground can be used to easily build a quick SDCAlertView alert to try
out its functionality.

Example.playground/Contents.swift

@@ -0,0 +1,14 @@
+import XCPlayground
+import SDCAlertView
+
+let viewController = UIViewController()
+viewController.view.backgroundColor = UIColor.whiteColor()
+
+XCPlaygroundPage.currentPage.liveView = viewController
+XCPlaygroundPage.currentPage.needsIndefiniteExecution = true
+
+/*** Create, customize, and present your alert below ***/
+
+let alert = AlertController(title: "Title", message: "Hey user, you're being alerted about something")
+alert.addAction(AlertAction(title: "OK", style: .Preferred))
+alert.present()

Example.playground/contents.xcplayground

@@ -0,0 +1,4 @@
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<playground version='5.0' target-platform='ios'>
+    <timeline fileName='timeline.xctimeline'/>
+</playground>

Example.playground/timeline.xctimeline

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<Timeline
+   version = "3.0">
+   <TimelineItems>
+   </TimelineItems>
+</Timeline>

Example/Base.lproj/Main.storyboard

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8" standalone="no"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="8191" systemVersion="15A284" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" initialViewController="uvy-DI-gcx">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="9059" systemVersion="15B42" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" initialViewController="uvy-DI-gcx">
     <dependencies>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="8154"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="9049"/>
         <capability name="Constraints to layout margins" minToolsVersion="6.0"/>
     </dependencies>
     <scenes>
@@ -261,11 +261,6 @@
                     </tableView>
                     <navigationItem key="navigationItem" id="nNM-ph-wei">
                         <nil key="title"/>
-                        <barButtonItem key="leftBarButtonItem" title="Custom" style="done" id="RcL-qa-89v">
-                            <connections>
-                                <action selector="presentCustomAlert" destination="z1T-n9-iqs" id="7op-iO-5zy"/>
-                            </connections>
-                        </barButtonItem>
                         <barButtonItem key="rightBarButtonItem" title="Show" style="done" id="lz1-K7-S4y">
                             <connections>
                                 <action selector="presentAlert" destination="z1T-n9-iqs" id="eCc-m4-Gl7"/>

Example/DemoViewController.swift

@@ -20,11 +20,6 @@ class DemoViewController: UITableViewController {
         }
     }
 
-
-    @IBAction private func presentCustomAlert() {
-        // This method can be used as a playground. Will be called from the Custom button.
-    }
-
     private func presentSDCAlertController() {
         let title = self.titleTextField.content
         let message = self.messageTextField.content