title: How do I denote content from curl's user flag (-u) in Typhoeus?
body: <p>I want to translate a curl request to a Typhoeus request.  Curl request:</p>
  
  <pre><code>@response = %x{curl -i https://track.customer.io/api/v1/customers/#{@client.id} \
          -X PUT \
          -H "Content-Type: application/json" \
          -u #{APP_CONFIG[:customerio][:api_key]}:#{APP_CONFIG[:customerio][:api_key]} \
          -d '{
            "email":"#{@client.email}",
            "name":"#{@client.name}",
            "id":"#{@client.id}",
            "created_at":"#{@client.created_at.to_time.to_i}"}'}
  </code></pre>
  
  <p>Typhoeus request:</p>
  
  <pre><code>request = Typhoeus::Request.new(
      "https://track.customer.io/api/v1/customers/4", 
      ssl_verifypeer: false,
      method: :put,
      headers: {
          "Content-Type" =&gt; "application/json",
          "user_agent" =&gt; "#{APP_CONFIG[:customerio][:api_key]}:#{APP_CONFIG[:customerio][:api_key]}"},
      body: '{
      "email":"first@last.com", 
      "name":"Name is here",
      "id":"4",
      "created_at":"#{Time.now}"}')
  </code></pre>
  
  <p>When I run the Typhoeus request, I get a response saying <code>unauthorized</code> which I believe indicates my user info is incorrect.  How can I set the -u flag equivalent in a Typhoeus request?</p>