[BUG] The config seems to be out of date #619

Describe the bug
A clear and concise description of what the bug is.

https://github.com/ncmpcpp/ncmpcpp/blob/master/doc/config

To Reproduce
Edit a new config and copy the example in, changing the directories and other things that need to be changed.

Expected behavior
The program runs without issue.

Screenshots/Logs
BASH output
"Unknown option: mpd_password"

(After re-commenting that out and entering in the password manually)

"Unknown option: visualizer_spectrum_smooth_look_legacy_chars"

Desktop (please complete the following information):

• LMDE6 (Debian)
• BASH
• MPD v. 0.23.12-1+b1
• NCMPCPP v. 0.9.2-2+b3

Additional context
Yes, technically I can leave those options commented out and it will work fine. However these options if left in should be updated to indicate that they are for older/legacy versions of MPD and may not work with the latest one (though I'll admit that "legacy_mpd_visualizer_spectrum_smooth_look_legacy_chars" does sound a bit silly.)

I'm also not sure what other options will trigger any other unknown opitons as those are the only two I've tested (so far.) Technically I don't even need the legacy_chars, I was just seeing what it would do. The password option would be nice though. Sure it's plaintext but entering in one each time is rather annoying when I could just use a randomly generated one that would be more secure anyway (though this is technically a different issue I guess unless I just don't know the modern syntax for the password field.)