安装intervention/image报错了，拜托大家指点下该怎么解决。
错误提示如下：
$ composer require intervention/image
Using version ^2.3 for intervention/image
./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
- Conclusion: remove laravel/framework v5.2.31
- Conclusion: don't install laravel/framework v5.2.31
- Can only install one of: laravel/framework[v5.2.28, v5.2.31].
- don't install laravel/framework v5.2.31|remove illuminate/config v5.2.28
- don't install illuminate/config v5.2.28|don't install laravel/framework v5 .2.31
- don't install illuminate/config v5.2.28|don't install laravel/framework v5 .2.31
- Installation request for laravel/framework (locked at v5.2.31, required as 5.2.*) -> satisfiable by laravel/framework[v5.2.31].
- Installation request for illuminate/config (locked at v5.2.28) -> satisfia ble by illuminate/config[v5.2.28], laravel/framework[v5.2.28].
Installation failed, reverting ./composer.json to its original content.
