Add watchOS and tvOS targets

Author: Christoph Hagen

SignalProtocolC.podspec

@@ -5,6 +5,8 @@ Pod::Spec.new do |s|
 
   s.osx.deployment_target = '10.9'
   s.ios.deployment_target = '8.0'
+  s.tvos.deployment_target = '9.0'
+  s.watchos.deployment_target = '2.0'
 
   s.description  = <<-DESC
                   This is a ratcheting forward secrecy protocol that works in synchronous and asynchronous messaging environments.