title: Composer error while trying to upgrade to Yii 2.0.15
body: <p>I tried to update my Yii but I receive this message:</p>
  
  <pre><code>[alexandre@Mac-mini-de-Alexandre:gestao_web (master)] php composer.phar require "yiisoft/yii2:~2.0.15" --update-with-dependencies
  ./composer.json has been updated
  Loading composer repositories with package information
  Updating dependencies (including require-dev)
  Your requirements could not be resolved to an installable set of packages.
  Problem 1
  - Installation request for yidas/yii2-composer-bower-skip (locked at 2.0.12, required as ~2.0.0) -&gt; satisfiable by yidas/yii2-composer-bower-skip[2.0.12].
  - yiisoft/yii2 2.0.15 requires bower-asset/inputmask ~3.2.2 | ~3.3.5 -&gt; satisfiable by yidas/yii2-composer-bower-skip[2.0.13].
  - yiisoft/yii2 2.0.15.1 requires bower-asset/inputmask ~3.2.2 | ~3.3.5 -&gt; satisfiable by yidas/yii2-composer-bower-skip[2.0.13].
  - Conclusion: don't install yidas/yii2-composer-bower-skip 2.0.13
  - Installation request for yiisoft/yii2 ~2.0.15 -&gt; satisfiable by yiisoft/yii2[2.0.15, 2.0.15.1].
  Installation failed, reverting ./composer.json to its original content.
  [alexandre@Mac-mini-de-Alexandre:gestao_web (master)] ./yii
  This is Yii version 2.0.12.2.
  </code></pre>
  
  <p>This is my <code>composer.json</code>:</p>
  
  <pre><code>{
      "name": "yiisoft/yii2-app-basic",
      "description": "Yii 2 Basic Application Template",
      "keywords": ["yii2", "framework", "basic", "application template"],
      "homepage": "http://www.yiiframework.com/",
      "type": "project",
      "license": "BSD-3-Clause",
      "support": {
          "issues": "https://github.com/yiisoft/yii2/issues?state=open",
          "forum": "http://www.yiiframework.com/forum/",
          "wiki": "http://www.yiiframework.com/wiki/",
          "irc": "irc://irc.freenode.net/yii",
          "source": "https://github.com/yiisoft/yii2"
      },
      "minimum-stability": "stable",
      "require": {
          "php": "&gt;=5.4.0",
          "yidas/yii2-composer-bower-skip": "~2.0.0",
          "yiisoft/yii2": "&gt;=2.0.7",        
          "yiisoft/yii2-bootstrap": "*",
          "yiisoft/yii2-swiftmailer": "*",
          "2amigos/yii2-resource-manager-component": "*",
          "moonlandsoft/yii2-phpexcel": "*",
          "boundstate/yii2-mailgun": "*",
          "e96/yii2-mailgun-mailer": "*"
      },
      "require-dev": {
          "yiisoft/yii2-codeception": "*",
          "yiisoft/yii2-debug": "*",
          "yiisoft/yii2-gii": "*",
          "yiisoft/yii2-faker": "*"
      },
      "config": {
          "process-timeout": 1800
      },
      "scripts": {
          "post-create-project-cmd": [
              "yii\\composer\\Installer::postCreateProject"
          ]
      },
      "extra": {
          "yii\\composer\\Installer::postCreateProject": {
              "setPermission": [
                  {
                      "runtime": "0777",
                      "web/assets": "0777",
                      "yii": "0755"
                  }
              ],
              "generateCookieValidationKey": [
                  "config/web.php"
              ]
          },
          "asset-installer-paths": {
              "npm-asset-library": "vendor/npm",
              "bower-asset-library": "vendor/bower"
          }
      }
  }
  </code></pre>
  
  <p>I tried change composer to it:</p>
  
  <pre><code>"yiisoft/yii2": "&gt;=2.0.12"
  </code></pre>
  
  <p>But I have the same error.</p>
  
  <p>Does anyone know what this problem might be? How can I fix?</p>