Your requirements could not be resolved to an installable set of packages.
Problem 1
- yiisoft/yii2 2.0.9 requires bower-asset/jquery 2.2.*@stable | 2.1.*@stable | 1.11.*@stable | 1.12.*@stable -> no matching package found.
- yiisoft/yii2 2.0.8 requires bower-asset/jquery 2.2.*@stable | 2.1.*@stable | 1.11.*@stable -> no matching package found.
- yiisoft/yii2 2.0.12 requires bower-asset/jquery 2.2.*@stable | 2.1.*@stable | 1.11.*@stable | 1.12.*@stable -> no matching package found.
- yiisoft/yii2 2.0.11.2 requires bower-asset/jquery 2.2.*@stable | 2.1.*@stable | 1.11.*@stable | 1.12.*@stable -> no matching package found.
- yiisoft/yii2 2.0.11.1 requires bower-asset/jquery 2.2.*@stable | 2.1.*@stable | 1.11.*@stable | 1.12.*@stable -> no matching package found.
- yiisoft/yii2 2.0.11 requires bower-asset/jquery 2.2.*@stable | 2.1.*@stable | 1.11.*@stable | 1.12.*@stable -> no matching package found.
- yiisoft/yii2 2.0.10 requires bower-asset/jquery 2.2.*@stable | 2.1.*@stable | 1.11.*@stable | 1.12.*@stable -> no matching package found.
- Installation request for yiisoft/yii2 >=2.0.8 -> satisfiable by yiisoft/yii2[2.0.10, 2.0.11, 2.0.11.1, 2.0.11.2, 2.0.12, 2.0.8, 2.0.9].
解决办法：composer global require "fxp/composer-asset-plugin:1.2.0"