v0.3.0

• StartStream now accepts optional query params.
  Example:

api.Stream.StartStream("?expansions=attachments.media_keys,referenced_tweets.id,author_id")

• GetMessages returns a struct which can contain an error from twitter, or it can contain your tweet bytes. It's now up to you to unmarshal the bytes into a struct your create.

	go func() {
		for message := range api.Stream.GetMessages() {
			if message.Err != nil {
				panic(message.Err)
			}
                        // Will print something like: 
                        //{"data":{"id":"1356479201000","text":"Look at this cat picture"},"matching_rules":[{"id":12345,"tag":"cat tweets with images"}]}
			fmt.Println(string(message.Data))
		}
	}()

• Updated ReadMe
• Add examples directory
• Add rulesResponseError as a possible error returned by rulesResponse. Learn more here: https://developer.twitter.com/en/support/twitter-api/error-troubleshooting