Table

Table构造函数调用Widget构造函数
Merge pull request #7 from yanyu0517/v0.3

new Table
Merge pull request #8 from rickyleung/v0.3

Button && classList
Merge pull request #9 from rickyleung/v0.3

更新文档，优化class添加方式
update readme
Merge pull request #1 from bizdevfe/v0.3

V0.3