Prompt can have bad interactions with some other plugins, like Ale

I am using [Ale](https://github.com/w0rp/ale) for async linting, which can update Vim in a way that messes up import JS when presented with the list of unresolved imports. This leaves Vim in a confusing state. Here's a demonstration:


I imagine there are other plugins that might have similar interactions.

I wonder if we could fix this by using a nicer prompt. It would be great to use a command-t style prompt where one option is highlighted and I can press enter to select it and use arrow keys to move up and down the list. This would pave the way to add fuzzy text filtering as well, which could be helpful when presented with a lot of options.