Fixed _BSMachError error and added updated podspec

Author: ArtSabintsev

CONTRIBUTORS.md

@@ -22,6 +22,7 @@
 - [attilat85](https://github.com/attilat85) for [Pull Request #124 (Harpy)](https://github.com/ArtSabintsev/Harpy/pull/124)
 - [Vahan Margaryan](https://github.com/VahanMargaryan) for [Pull Request #71](https://github.com/ArtSabintsev/Siren/pull/71)
 - [Josip Injic](https://github.com/jinjic) for [Pull Request #73](https://github.com/ArtSabintsev/Siren/pull/73)
+- [Thi](https://github.com/thii) for [Pull Request #78](https://github.com/ArtSabintsev/Siren/pull/78)
 
 ### Harpy Project Contributors
 This repo is a Swift language port of [Harpy](http://github.com/ArtSabintsev/Harpy). We couldn't have built this port without acknowledging the following developers who were instrumental in getting Harpy to v3.2.1, the version of Harpy that Siren was based on.

README.md

@@ -171,7 +171,7 @@ public protocol SirenDelegate: class {
 ```
 
 ## Localization
-Harpy is localized for Arabic, Armenian, Basque, Chinese (Simplified), Chinese (Traditional), Danish, Dutch, English, Estonian, French, German, Hebrew, Hungarian, Italian, Japanese, Korean, Latvian, Lithuanian, Malay, Polish, Portuguese (Brazil), Portuguese (Portugal), Russian, Slovenian, Swedish, Spanish, Thai, and Turkish.
+Harpy is localized for Arabic, Armenian, Basque, Chinese (Simplified), Chinese (Traditional), Danish, Dutch, English, Estonian, French, German, Hebrew, Hungarian, Italian, Japanese, Korean, Latvian, Lithuanian, Malay, Polish, Portuguese (Brazil), Portuguese (Portugal), Russian, Slovenian, Swedish, Spanish, Thai, Turkish, Vietnamese.
 
 You may want the update dialog to *always* appear in a certain language, ignoring iOS's language setting (e.g. apps released in a specific country).
 

Siren.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "Siren"
-  s.version      = "0.9.3"
+  s.version      = "0.9.4"
   s.summary      = "Notify users when a new version of your iOS app is available, and prompt them with the App Store link.."
 
   s.description  = <<-DESC

Siren/Siren.swift

@@ -621,7 +621,10 @@ private extension Siren {
 
         let iTunesString =  "https://itunes.apple.com/app/id\(appID)"
         let iTunesURL = NSURL(string: iTunesString)
-        UIApplication.sharedApplication().openURL(iTunesURL!)
+
+        dispatch_async(dispatch_get_main_queue()) { 
+            UIApplication.sharedApplication().openURL(iTunesURL!)
+        }
     }
 
     func printMessage(message: String) {