removed depricated --dev from composer

Author: pulkitjalan

.travis.yml

@@ -10,7 +10,7 @@ php:
 
 before_script:
   - travis_retry composer self-update
-  - travis_retry composer install --no-interaction --prefer-source --dev
+  - travis_retry composer install --no-interaction --prefer-source
 
 script:
   - phpunit --coverage-text --coverage-clover=coverage.clover

src/GeoIPUpdater.php

@@ -2,8 +2,8 @@
 
 namespace PulkitJalan\GeoIP;
 
-use GuzzleHttp\Client as GuzzleClient;
 use Exception;
+use GuzzleHttp\Client as GuzzleClient;
 
 class GeoIPUpdater
 {
@@ -30,7 +30,7 @@ public function __construct(array $config, GuzzleClient $guzzle = null)
     /**
      * Main update function.
      *
-     * @return bool|string
+     * @return string|false
      */
     public function update()
     {
@@ -70,8 +70,8 @@ protected function updateMaxmindDatabase()
     /**
      * gzdecode function.
      * 
-     * @param mixed $data
-     * @return mixed
+     * @param \Psr\Http\Message\StreamInterface $data
+     * @return string
      */
     protected function gzdecode($data)
     {