[Feacture request] Read from stdin

[bertinatto]

First of all, thank you so much for neovim-gtk! I really hope the project keeps going.

Right now I only miss 1 thing to make neovim-gtk my default editor, and that's the ability to do:

echo blah | nvim-gtk -

I'd love to be able to do that.

[daa84]

Interesting in typical use case for this feature? Current implementation does not require - argument.

[bertinatto]

@daa84, I'm not sure if I understand your question, but I tested the build from branch pipe-input and it works great!

Thanks for this!

[daa84]

Merged to master