fix warning about header cast, fix podspec

DTTableViewManager.podspec

@@ -7,7 +7,7 @@ Pod::Spec.new do |s|
   s.authors  = { 'Denys Telezhkin' => 'denys.telezhkin@yandex.ru' }
   s.social_media_url = 'https://twitter.com/DTCoder'
   s.source   = { :git => 'https://github.com/DenHeadless/DTTableViewManager.git', :tag => s.version.to_s }
-  s.source_files = 'DTTableViewManager'
+  s.source_files = 'DTTableViewManager/**/*.{h,swift}'
   s.requires_arc = true
   s.ios.deployment_target = '8.0'
   s.ios.frameworks = 'UIKit', 'Foundation'

DTTableViewManager/TableViewFactory.swift

@@ -143,16 +143,24 @@ class TableViewFactory
     func headerFooterViewWithMapping(mapping: ViewModelMapping, unwrappedModel: Any) -> UIView?
     {
         let viewClassName = RuntimeHelper.classNameFromReflection(mapping.viewTypeMirror)
-        var view = self.tableView.dequeueReusableHeaderFooterViewWithIdentifier(viewClassName) as? UIView
-        if view == nil {
+        if let view = self.tableView.dequeueReusableHeaderFooterViewWithIdentifier(viewClassName) {
+            mapping.updateBlock(view,unwrappedModel)
+            return view
+        }
+        else {
+            let view : UIView?
             if let type = mapping.viewTypeMirror.value as? UIView.Type {
                 view = type.dt_loadFromXibInBundle(bundle)
             }
+            else {
+                view = nil
+            }
+
+            precondition(view != nil,"failed creating view of type: \(viewClassName) for model: \(unwrappedModel)")
+
+            mapping.updateBlock(view!,unwrappedModel)
+            return view
         }
-        precondition(view != nil,"failed creating view of type: \(viewClassName) for model: \(unwrappedModel)")
-
-        mapping.updateBlock(view!,unwrappedModel)
-        return view
     }
 
     private func headerFooterViewOfType(type: ViewType, model : Any) -> UIView?