Update podspec.

Author: inamiy

SwiftState.podspec

@@ -1,14 +1,16 @@
 Pod::Spec.new do |s|
   s.name     = 'SwiftState'
-  s.version  = '3.0.1'
+  s.version  = '4.0.0'
   s.license  = { :type => 'MIT' }
   s.homepage = 'https://github.com/ReactKit/SwiftState'
   s.authors  = { 'Yasuhiro Inami' => '[email protected]' }
   s.summary  = 'Elegant state machine for Swift.'
   s.source   = { :git => 'https://github.com/ReactKit/SwiftState.git', :tag => "#{s.version}" }
-  s.source_files = 'SwiftState/**/*.{h,swift}'
+  s.source_files = 'Sources/**/*.swift'
   s.requires_arc = true
 
   s.osx.deployment_target = '10.9'
   s.ios.deployment_target = '8.0'
+  s.watchos.deployment_target = '2.0'
+  s.tvos.deployment_target = '9.0'
 end