Merge pull request #40 from ilife5/master

完成dropdown menu部分，增加相应的例子
by qianjun;�����ĵ�������
by qianjun;add doc,more examples
by qianjun;add doc,more examples
by qianjun;change console.log to valon.log
by qianjun;change console.log to valon.log
Merge pull request #41 from gogoyqj/master

完成tab组件
Merge pull request #42 from ilife5/master

完成dropdown的初始化及定位功能
Merge pull request #6 from RubyLouvre/master

merge from master