Change <var> to VAR throughout

[rkdarst]

• As discussed in chat (but not yet agreed)
• Ran the command sed -i -E 's/<([0-9a-zA-Z_-]+)>/\U\1/g' content/*.md but also checked each with "meld" and removed cases
  that shouldn't be changed (like git command outputs)
  • If git command hints use <var> maybe that's a reason to not
    change?
• Also changed some cases which weren't in angle brackets yet.
• Time taken: about 5 minutes.
• Review
  • There's a real chocie here: is this a good idea or not? I'm not
    sure, I've done this to see how hard it would be, not because it
    should be done.
  • Advantages: perhaps more clear what should be replaced and that
    <> are not part of the syntax? Upper case easier to scan and
    see?
  • Disadvanages: unclear what is a replacement and what is not? (I
    didn't see any places that wolud be the case.) Different than
    what others use?
  • The biggest disadvantage is that HEAD is actually a literal that
    is used in git... which is ambiguous.

[rkdarst]

The confusion about HEAD is the biggest problem, I think. It's enough to make me really doubt this, until we either decide that's OK or compensate somehow. But I'm not sure it's worth it.

[bast]

For me this change makes it better and easier to follow. Maybe we can avoid using HEAD? EDIT: avoid using it in commands?

[bast]

• it is easier to read
• less risk to break hedgedoc if somebody copy pastes a command

[bast]

Thank you!