minor update to cocoapods example

Examples/Cocoapods/NaturalLanguage/.gitignore

@@ -0,0 +1,4 @@
+NaturalLanguage/*.pb.swift
+NaturalLanguage/*.grpc.swift
+
+googleapis/

Examples/Cocoapods/NaturalLanguage/Podfile

@@ -1,10 +1,12 @@
 # Uncomment this line if you're using Swift
 use_frameworks!
 
-target 'NaturalLanguage' do
+platform :ios, '9.0'
 
+target 'NaturalLanguage' do
   pod 'SwiftGRPC'
-
 end
 
-
+post_install do |installer|
+  %x[ './RUNME' ]
+end

Examples/Cocoapods/NaturalLanguage/README.md

@@ -5,13 +5,13 @@ This directory contains a very simple sample that calls the
 Calls are made directly to the Cloud Natural Language RPC interface. 
 In practice, these would be wrapped in idiomatic code.
 
-1. Use [RUNME](RUNME) to generate the necessary Protocol Buffer
-and gRPC support code. It uses protoc and the Swift Protocol
-Buffer and gRPC plugins, so please be sure these are in your
-path. The plugins can be built by running `make` in the 
-top-level grpc-swift directory.
+1. Run `pod install` to install the SwiftGRPC pod and its dependencies.
 
-2. Run `pod install` to install the SwiftGRPC pod and its dependencies.
+2. Running `pod install` will invoke [RUNME](RUNME) to generate the 
+necessary Protocol Buffer and gRPC support code. It uses protoc and 
+the Swift Protocol Buffer and gRPC plugins, so please be sure these 
+are in your path. The plugins can be built by running `make` in the 
+top-level grpc-swift directory.
 
 3. Open NaturalLanguage.xcworkspace and set GOOGLE_API_KEY in the application delegate.