Add delete confirmation

[moughxyz]

From user:

Hello,

first thank you very much for your work, I really enjoy using Standard
Notes!

I was deleting a few of my first "lets try it out" Notes when I noticed,
that when doing so on linux I had to confirm that I really wanted to
delete a Note which makes sense so that one doesn't delete anything
accidentally. Since I'm using the Android Beta on my phone too I deleted
another Note later there but there weren't asked any questions.
I know that mobile apps aren't a priority but I was just thinking that a
pop-up of some kind just like on linux would be great. Its not hard to
make such mistakes on a phone and it would be a bit annoying to loose
important stuff because of it.

[deftelf]

40983d875727cd521939270ac1609c9b0921a199