Escape on empty search buffer should exit search

[verhovsky]

Is your feature request related to a problem? Please describe.
I hate that when I open the search bar when I didn't mean to (or when I'm just exploring what telescope, or specificically the neovim distro that's using it, offers), I have to press escape twice to exit.

Describe the solution you'd like
It should be a special case that when you haven't typed anything in the search box, escape should exit the search instead of going to Normal mode and having the next escape close the search box. I use the system clipboard, so there is not a single reason why I would want to enter Normal mode on an empty buffer, other than to press escape a second time.