fzf#run: improve "is already running" message (#885)
fzf#run: improve "is already running" message (#885)

This displays the buffer(s) in this case, which is useful when FZF got
stuck, and you have to manually remove the buffer.
janlazo/fzf,junegunn/fzf,infokiller/fzf,infokiller/fzf,wilywampa/fzf,wilywampa/fzf,wilywampa/fzf,infokiller/fzf,janlazo/fzf,junegunn/fzf,tomfitzhenry/pkg-fzf,janlazo/fzf,stuha/wbr-zsh,junegunn/fzf,tomfitzhenry/pkg-fzf,tomfitzhenry/pkg-fzf