composer [ReflectionException] Class FxpComposerAssetPluginRepositoryNpmRepository does not exist

在执行composer update时报错

[ReflectionException]
Class FxpComposerAssetPluginRepositoryNpmRepository does not exist

是因为 fxp/composer-asset-plugin 升级导致的，所以只要升级 fxp/composer-asset-plugin 就可以解决

composer global update fxp/composer-asset-plugin --no-plugins


FROM：
http://stackoverflow.com/questions/36437837/composer-throw-reflectionexception-class-fxp-composer-assetplugin-repository-n