Misc dev env fixes

[rvl]

Issue Number

Found while working on #2765.

Overview

This is a mixed bag of small tweaks.

• Adds .dir-locals.el with conservative presets for Emacs users.
• Add tracing of job names to Hydra evaluation (thanks for the tip @hamishmack)
• Delete some unneeded code in shell.nix (thanks for the tip @jbgi @nrdxp)
• Change scripts/gen-hie.sh to make symlinks if hie.yaml and .ghci don't exist.
• .gitignore and .editorconfig tweaks.

[sevanspowell]

Suggestion: I think I'd prefer if this file was renamed to .dir-locals.el.example or something similar. It's super useful to mine for ideas, but quickly diverges between programmers, and I can't imagine dealing with the merge conflicts being fun, you'd have to stash your local changes every time you pull then pop them afterwards?

That way we could contribute ideas to the example file without having to worry about breaking other's configs.

[rvl]

Yes you're right.
I will remove it, and use its text as an example in our documentation.
It would be nice to have editors working properly "out of the box."
With VSCode, you can add stuff like recommended plugins and settings into the .vscode directory.
But perhaps this is too difficult to do for emacs.

[sevanspowell]

Ooh, what makes this not necessary anymore?

[rvl]

I put a link in the commit message to this: NixOS/nixpkgs#103501

[sevanspowell]

Thank you 👍

[rvl]

bors r+

[iohk-bors]

Build failed:

• ci/hydra-build:required

Failures:

  src/Test/Integration/Scenario/CLI/Network.hs:94:11: 
  1) CLI Specifications, COMMON_CLI_NETWORK, CLI_NETWORK - cardano-wallet network information
[cardano-wallet.network:Warning:50634] [2021-07-20 03:54:48.65 UTC] Connection lost with the node. Network.Socket.recvBuf: resource vanished (Connection reset by peer)
[cardano-wallet.network:Warning:50817] [2021-07-20 03:54:48.65 UTC] Connection lost with the node. Network.Socket.recvBuf: resource vanished (Connection reset by peer)
[cardano-wallet.network:Warning:50752] [2021-07-20 03:54:48.65 UTC] Connection lost with the node. Network.Socket.recvBuf: resource vanished (Connection reset by peer)
[cardano-wallet.network:Warning:50692] [2021-07-20 03:54:48.66 UTC] Connection lost with the node. Network.Socket.recvBuf: resource vanished (Connection reset by peer)
[cardano-wallet.network:Warning:2297] [2021-07-20 03:54:48.66 UTC] Connection lost with the node. writev: resource vanished (Broken pipe)
       expected: ExitSuccess
        but got: ExitFailure 1

  To rerun use: --match "/CLI Specifications/COMMON_CLI_NETWORK/CLI_NETWORK - cardano-wallet network information/"

Randomized with seed 276448537

Finished in 1568.1199 seconds, used 1779.6449 seconds of CPU time
837 examples, 1 failure, 25 pending

#2855