blog/nix-flakes-*.markdown problems

[deemp]

Hi! @Xe, I'd like to ask you to update the article since it's pinned on the nix flakes page.

Here is a list of problems which I've encountered while reading the article.

part 1

1. #519 - flake.nix has a bit different content now
2. nix develop doesn't enter a shell. There doesn't appear a prefix like [cadey@pneuma:~/tmp/gohello]$
3. nix develop doesn't work for xess example unless I add it to the outputs like here

part 2

1. Can't run the web-server via nix run