添加一个简易的css sprite构建器
callback提出来
加测试用例，调整了一下代码结构
Merge branch 'feature/css-spriter' of github.com:quyatong/edp-build into feature/css-spriter
修了fecs报的规范问题，调整了一下代码结构
Merge branch 'quyatong-feature/css-spriter' into 1.0/develop
bump to 1.0.15-beta.6