title: Alamofire post request doesn't work?
body: <p>I'm using alamofire latest version(swift 3), my pod installation like below,</p>
  
  <pre><code>pod 'Alamofire', :git =&gt; 'https://github.com/Alamofire/Alamofire.git', :branch =&gt; 'master'
  </code></pre>
  
  <p>And I'm trying to send a request as below, it worked for alamofire previous versions. However it doesn't work with this version.</p>
  
  <p>In my opinion, the parameters are not sent properly.</p>
  
  <pre><code> let param: Parameters = ["grant_type": "password",
                   "username": "0767898037",
                   "password" : "Hammer@123"]
      NSLog("param \(param))")
      Alamofire.request("http://api.xxxx.com/token" , method: .post, parameters: param , encoding: JSONEncoding.default).responseJSON { response in
          NSLog("res \(response.request))")
          switch response .result {
  
          case .success(let JSON) :
              NSLog("values \(response.result.value))")
              let response2 = JSON as! NSDictionary
               NSLog("values22 \(response2.value(forKeyPath: "access_token")))")
          case .failure(let error) :
              NSLog("errr \(response.result.value))")
              NSLog("error \(error))")
              let error = error as Error
              print(error.localizedDescription)
          }
      }
  </code></pre>
  
  <p>I'm getting an error in the console as follows:</p>
  
  <pre><code>2017-03-21 18:21:42.572362 com.sodesync.dudget.iOSClient[5927:1259497] values Optional({
  error = "unsupported_grant_type";
  }))
  </code></pre>