Please update to support laravel 7.x

[zishang520]

Problem 1
- codingyu/ueditor 3.0.0 requires codingyu/laravel-ueditor ~2.0 -> satisfiable by codingyu/laravel-ueditor[2.0.0].
- Installation request for codingyu/ueditor ^3.0 -> satisfiable by codingyu/ueditor[3.0.0].
- Conclusion: remove laravel/framework v7.0.4
- Conclusion: don't install laravel/framework v7.0.4
- codingyu/laravel-ueditor 2.0.0 requires laravel/framework ~5.5|~6.0 -> satisfiable by laravel/framework[5.5.x-dev, 5.6.x-dev, 5.7.x-dev, 5.8.x-dev, 6.x-dev].
- Can only install one of: laravel/framework[5.5.x-dev, v7.0.4].
- Can only install one of: laravel/framework[5.6.x-dev, v7.0.4].
- Can only install one of: laravel/framework[5.7.x-dev, v7.0.4].
- Can only install one of: laravel/framework[5.8.x-dev, v7.0.4].
- Can only install one of: laravel/framework[6.x-dev, v7.0.4].
- Installation request for laravel/framework (locked at v7.0.4, required as ^7.0) -> satisfiable by laravel/framework[v7.0.4].

[codingyu]

已经更新了 codingyu/laravel-ueditor 的版本依赖，可以安装了