modal.confirm与modal.prompt样例代码错误

[putisoft]

https://weex.apache.org/zh/docs/modules/modal.html#confirm
和
https://weex.apache.org/zh/docs/modules/modal.html#prompt
这两个样例中，不应该出现duration，而应该以okTitle或cancelTitle。
这两个都是模态对话框，不可能有duration参数的。

另，modal.confirm的callback若以布尔型结果，表示点击确定或取消为更好，这样代码通用性更强，逻辑上也更合理。

[YorkShen]

感谢你的反馈，Weex目前是隶属于Apache Software Foundation的项目，因此在Gtihub渠道我们鼓励使用英文反馈问题。下面我将使用Google Trasnlate将你的问题翻译成英语，并以英语回答。

Question Description: https://weex.apache.org/en/docs/modules/modal.html#confirm and https://weex.apache.org/en/docs/modules/modal.html#prompt In these two examples, There should be no duration, but okTitle or cancelTitle. Both of these are modal dialogs and there is no possibility of a duration parameter. In addition, if the modal.confirm callback has a Boolean result, it means that clicking OK or cancel is better, so the code is more versatile and logically more reasonable.

Please give us a PR, thanks.