Allow disabling LED usage in config

[aveao]

Heyo,

I plan to have a cronjob running on a homeserver to get me an album of the screenshots I take, and having the LED flash every minute or so would make it pretty annoying, so I implemented the ability to disable the LED flashing in config.

I've tested this and well, it works.

I've also:

• Dropped mpg123 requirement. This isn't required anymore as sys-ftpd has no audio playback.
• Moved connect LED action to only when there's a successful authentication, so that random unsuccessful connections (if they do happen) won't cause any flashing. (This change also makes it easier to integrate it into my modifications.)

[aveao]

Also, as a personal request... can you run a linter/formatter on the whole codebase? I was unable to stick to the code style as some lines were space intended, some tab indented, some lines had spaces on their end etc.

[cathery]

let's get this bread

[cathery]

The whole codebase is a hackjob, i'll probably run it through a formatter in a bit