Deadlock on supplementary nodes (#36)

* Fix for block on main thread when using supplementary nodes

* 0.4.1

* 0.4.1

Author: foxware00

.swift-version

@@ -1,3 +1,4 @@
+
 ## RxASDataSources
 
 [![Platforms](https://img.shields.io/cocoapods/p/RxASDataSources.svg)](https://cocoapods.org/pods/RxASDataSources)
@@ -12,8 +13,8 @@
 - [Features](#features)
 - [Requirements](#requirements)
 - [Installation](#installation)
-    - [CocoaPods](#cocoapods)
-    - [Carthage](#carthage)
+  - [CocoaPods](#cocoapods)
+  - [Carthage](#carthage)
 - [Usage](#usage)
 - [License](#license)
 
@@ -27,9 +28,9 @@
 
 ## Requirements
 
-- iOS 8.0+
-- Xcode 9.0+
-- RxSwift 4.0 & Texture 2.5
+- iOS 9.0+
+- Xcode 10.1+
+- RxSwift 5.0 & Texture 2.8
 
 ## Installation
 

Readme.md

@@ -1,16 +1,16 @@
 Pod::Spec.new do |s|
      s.name = 'RxASDataSources'
-     s.version = '0.3.4'
+     s.version = '0.4.1'
      s.license = { :type => "MIT", :file => "LICENSE" }
      s.summary = 'RxDataSources for AsyncDisplayKit/Texture supports ASTableNode/ASCollectionNode'
      s.homepage = 'https://github.com/RxSwiftCommunity/RxASDataSources'
      s.social_media_url = 'https://twitter.com/dangthaison91'
      s.authors = { "Dang Thai Son" => "[email protected]" }
      s.source = { :git => "https://github.com/RxSwiftCommunity/RxASDataSources.git", :tag => s.version.to_s }
 
-     s.ios.deployment_target = '8.0'
+     s.ios.deployment_target = '9.0'
      s.requires_arc = true
-     s.swift_version = '5.0'
+     s.swift_versions = '5.0'
 
      s.source_files  = "Sources/**/*.swift"
      s.framework  = "Foundation"

RxASDataSources.podspec

@@ -36,7 +36,8 @@ open class ASCollectionSectionedDataSource<S: SectionModelType>: NSObject, ASCol
 
     fileprivate static func configureSupplementaryViewBlockNotSet(dataSource: ASCollectionSectionedDataSource<S>, node: ASCollectionNode, nodeForSupplementaryElementOfKind kind: String, indexPath: IndexPath) -> ASCellNodeBlock {
         // Users expect collectionNode(_nodeForSupplementaryElementOfKind:at:) will be executed in main thread according to api doc.
-        return { DispatchQueue.main.sync(execute: { dataSource.collectionNode(node, nodeForSupplementaryElementOfKind: kind, at: indexPath) }) }
+        let cellNode = dataSource.collectionNode(node, nodeForSupplementaryElementOfKind: kind, at: indexPath)
+        return { cellNode }
     }
 
     public init(