Updated pod spec to include C++ files

Author: j-sid

GTXiLib.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "GTXiLib"
-  s.version      = "4.1"
+  s.version      = "4.2"
   s.summary      = "iOS Accessibility testing library."
   s.description  = <<-DESC
   iOS Accessibility testing library that works with XCTest based frameworks.
@@ -9,9 +9,9 @@ Pod::Spec.new do |s|
   s.license      = "Apache License 2.0"
   s.author       = "j-sid"
   s.platform     = :ios
-  s.source       = { :git => "https://github.com/google/GTXiLib.git", :tag => "4.1.0" }
+  s.source       = { :git => "https://github.com/google/GTXiLib.git", :tag => "4.2.0" }
   s.source_files = "{Classes,OOPClasses}/**/*.{h,m,swift,mm,cc}"
   s.ios.deployment_target = '9.0'
   s.libraries = 'c++'
   s.dependency 'Protobuf-C++'
-end
+end