title: Curl request with params to Guzzle
body: <p>I'm working on <code>Laravel 5.2</code> with <code>Guzzle 6.2</code>, and I have this CURL request : </p>
  
  <pre><code>curl -X POST "https://api.lifebot.fr/letters" \
    -u "test_12345678901234567890:" \
    -d '{
     "description": "Demo Letter 1",
     "to": {
      "name": "LIFEBOT",
      "address_line1": "30 rue de la république",
      "address_city": "Paris",
      "address_postalcode": "75015",
      "address_country": "France"
     },
     "color" : "color",
     "postage_type" : "prioritaire",
     "from": {
      "name": "LIFEBOT",
      "address_line1": "30 rue de la république",
      "address_city": "Paris",
      "address_postalcode": "75015",
      "address_country": "France"
     },
     "source_file": "&lt;html style=\"padding-top: 3px; margin: 0.5px;\"&gt;Lettre HTML for {{name}}&lt;\/html&gt;",
     "source_file_type": "html",
     "variables" : {
      "name" : "Lifebot"
     }
  }'
  </code></pre>
  
  <p>This request is OK if KI use a terminal for testing.</p>
  
  <p>So, the params -u is my API key, and -d is datas to sent to the API.
  How can I convert this with Guzzle ?</p>
  
  <p>I tried something like : </p>
  
  <pre><code>$result = $client-&gt;request('GET',
            'https://api.lifebot.fr/', [
            'u' =&gt; 'test_12345678901234567890'
            ]);
  </code></pre>
  
  <p>Wha'ts the syntax with Guzzle for add my param -u and my param -d ?</p>