Fix assignment msgno to uid regardless of fetch_options is set in config (#39)

* Fix uid assigning logic

```Message:: __construct(...);``` without ```fetch_options``` parameter caused running ```imap_msgno``` function even ```FT_UID``` is set in config.

* Fix wrong option assignment  logic

The alternative branch will never be called.

* Update CHANGELOD.md

Author: parshikov

CHANGELOG.md

@@ -6,13 +6,13 @@ Updates should follow the [Keep a CHANGELOG](http://keepachangelog.com/) princip
 
 ## [UNRELEASED]
 ### Fixed
-- NaN
+- Fix assignment ```msgno``` to ```uid``` regardless of ```fetch_options``` is set in config 
 
 ### Added
 - NaN
 
 ### Affected Classes
-- All
+- [Message::class](src/IMAP/Message.php)
 
 ## [1.0.3.6] - 2017-10-24
 ### Added

src/IMAP/Message.php

@@ -127,11 +127,12 @@ class Message {
      * @param $fetch_options
      */
     public function __construct($uid, $msglist, Client $client, $fetch_options = null) {
+        $this->setFetchOption($fetch_options);
+        
         $this->msglist = $msglist;
         $this->client = $client;
-        $this->uid = ($fetch_options == FT_UID) ? $uid : imap_msgno($this->client->getConnection(), $uid);
-
-        $this->setFetchOption($fetch_options);
+        $this->uid = ($this->fetch_options == FT_UID) ? $uid : imap_msgno($this->client->getConnection(), $uid);
+        
         $this->parseHeader();
         $this->parseBody();
     }
@@ -454,7 +455,6 @@ protected function fetchAttachment($structure, $partNumber){
      * @return $this
      */
     public function setFetchOption($option){
-        $option = (integer)$option;
         if(is_long($option) == true){
             $this->fetch_options = $option;
         }elseif(is_null($option) == true){