Fix the attachments staying in the form on create-post
Fix the attachments staying in the form on create-post

`this.refs.commentsDisabled` is undefined when "More" is not open,
so there was a JS error. And we actually don't need that line anyway,
since checkbox is getting reset on closing "More" (`isMoreOpen: false`,
3 lines below).

clbn/freefeed-gamma,clbn/freefeed-gamma,clbn/freefeed-gamma,ujenjt/freefeed-react-client,kadmil/freefeed-react-client,davidmz/freefeed-react-client,kadmil/freefeed-react-client,FreeFeed/freefeed-react-client,kadmil/freefeed-react-client,ujenjt/freefeed-react-client,FreeFeed/freefeed-react-client,davidmz/freefeed-react-client,FreeFeed/freefeed-react-client,ujenjt/freefeed-react-client,FreeFeed/freefeed-html-react,FreeFeed/freefeed-html-react,FreeFeed/freefeed-html-react,davidmz/freefeed-react-client