Add netrc export option

[Millak]

This adds a netrc exporter type to keepassxc-cli and tries to create a netrc file which can be read by other programs.

Fixes #13380

Testing strategy

I copied tests/TestCsvExporter.* to tests/TestNetrcExporter.* and modified and removed tests as necessary.

Type of change

• ✅ New feature (change that adds functionality)

[varjolintu]

I'm pretty sure these persons did not have anything to do with your source and header files. Check them all.

[Millak]

I'm not always sure which copyright headers to keep and which to toss when I've started by copying another file and then modifying it.

[droidmonkey]

I dont necessarily like that this is an export option and not a format option against the show command. You are essentially dumping the entire contents of your database into another program so it may use one of the entries. Why use KeePassXC in the first place? netrc is the 1990s way to manage credentials.

[Millak]

I dont necessarily like that this is an export option and not a format option against the show command. You are essentially dumping the entire contents of your database into another program so it may use one of the entries.

That's a good way of phrasing it. The output is meant to be ephemeral, so show would be better, and it would only return the actual entry desired.

[varjolintu]

Closed because you made a duplicate: #13387