undefined poll when direct to the single poll page just after creating a poll

[GuoXiaoyang]

It seems that when I create a poll on the polls page, then I click the 'see this poll' button, the single poll page is under a 'undefined' path, and the page is always loading unless I go back to the home page and see this poll again.

Another question: one person can vote for one poll for unlimited times, I think it's unsuitable... Just a suggestion.

[GuoXiaoyang]

Sorry, I did't see the previous issue. You can just ignore my suggestion.

[Createdd]

@GuoXiaoyang Thanks! Feel free to open a PR if you want ;)