Bump podspec for v2.0.0.alpha3

Advance.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "Advance"
-  s.version      = "2.0.0.alpha2"
+  s.version      = "2.0.0.alpha3"
   s.summary      = "Physics-based animations for iOS, tvOS, and macOS."
   s.description  = "Advance is a Swift framework that enables advanced animations and physics-based interactions."
 
@@ -11,11 +11,11 @@ Pod::Spec.new do |s|
   s.authors      = "Tim Donnelly"
   s.social_media_url = 'http://twitter.com/timdonnelly'
 
-  s.source       = { :git => "https://github.com/timdonnelly/Advance.git", :tag => "v2.0.0.alpha2" }
+  s.source       = { :git => "https://github.com/timdonnelly/Advance.git", :tag => "v2.0.0.alpha3" }
 
   s.source_files = "Source/**/*.swift"
 
   s.ios.deployment_target = "10.0"
-  s.macos.deployment_target = "10.12"
+  s.osx.deployment_target = "10.12"
   s.tvos.deployment_target = "10.0"
 end