Update docs so folks copy/pasting with package managers will get updates.

Reading the docs for both ~> 1.0 means any 1.x.y but not up to 2.0,
which seems like the safe thing to spell out. Since we don't intend
to do anything api breaking in the 1.x versioning, hopefully set
folks up on the right things if they copy/paste.

Author: thomasvl

README.md

@@ -191,7 +191,7 @@ If you're using CocoaPods, add this to your `Podfile` adjusting the `:tag` to
 match the `[tag_name]` you used to build the plugin above:
 
 ```ruby
-pod 'SwiftProtobuf', '~> 1.0.1'
+pod 'SwiftProtobuf', '~> 1.0'
 ```
 
 And run `pod install`.
@@ -203,7 +203,7 @@ And run `pod install`.
 If you're using Carthage, add this to your `Cartfile` but adjust the tag to match the `[tag_name]` you used to build the plugin above:
 
 ```ruby
-github "apple/swift-protobuf" "1.0.1"
+github "apple/swift-protobuf" ~> 1.0
 ```
 
 Run `carthage update` and drag `SwiftProtobuf.framework` into your Xcode.project.