updated podspec to version 3

Swifter.podspec

@@ -9,7 +9,7 @@ Pod::Spec.new do |s|
   s.ios.deployment_target = "8.0"
   s.osx.deployment_target = "10.9"
   s.tvos.deployment_target = "9.0"
-  s.source                = { :git => "https://github.com/glock45/swifter.git", :tag => "1.2.6" }
+  s.source                = { :git => "https://github.com/glock45/swifter.git", :tag => "3.0.0" }
   s.source_files          = 'Sources/*.{h,m,swift}'
 
 end