More characters for polling

Thanks for the suggestion ​@AndrzejS 👍

I totally understand how you’d appreciate more characters overall. But just in case, I wanted to share our character limit guide that outlines everything. 

And for the time being, a poll question is allowed 256 characters. But if you add a description to the poll, that actually gives you another 256 characters. It’s not the same as having 500 characters allowed in the poll, but I thought I’d share that just in case.