[Installer] Print a post-install message

lib/cocoapods/installer.rb

@@ -462,6 +462,16 @@ module Pod
       run_plugins_post_install_hooks
       warn_for_deprecations
       lock_pod_sources
+      print_post_install_message
+    end
+
+    def print_post_install_message
+      podfile_dependencies = podfile.dependencies.uniq.size
+      pods_installed = root_specs.size
+      UI.info('Pod installation complete! ' \
+              "There #{podfile_dependencies == 1 ? 'is' : 'are'} #{podfile_dependencies} " \
+              "#{'dependency'.pluralize(podfile_dependencies)} from the Podfile " \
+              "and #{pods_installed} total #{'pod'.pluralize(pods_installed)} installed.")
     end
 
     # Runs the registered callbacks for the plugins post install hooks.