Add maximum expiry

[HeapUnderfl0w]

This aims to implement #54, and also be an improvement over #55.

Changes Made:

• Add WASTEBIN_MAX_PASTE_EXPIRY WASTEBIN_MAX_PASTE_EXPIRATION
• Ensure both the form and json routes honor the set limit (if any) (currently not done by add maximum expiration logic #55)
  • Currently it simply clamps the expiry time
  • Invalid values or too large values will cause an error
• Remove invalid options from the new-paste UI
  • Correctly hide never expire if any limit is set
  • Always show burn, even if the limit is 0
  • Default select the "top" most expiry (either "never", or 10 minutes)

[matze]

In general, looks good, just some questions.

[bt-nia]

thanks @HeapUnderfl0w ! 🎉 This certainly looks more sophisticated than what I did.
Hopefully this one sees more traction in terms of approval :)

[matze]

Hopefully this one sees more traction in terms of approval :)

Don't worry, I wasn't outright rejecting your proposal. A few more iterations and it would've landed. But yes, let's go with this one here.

[HeapUnderfl0w]

This should be all of the concerns addressed.

[HeapUnderfl0w]

@matze currently the json endpoints silently clamp the expiration value to the maximum.

Would you want to error out of here too? (some kind of http error)
Id personally would want to leave them as-is, as they are more advanced APIs anyway.

[matze]

Just the tiny end user clarification, rest looks good.

[matze]

Id personally would want to leave them as-is, as they are more advanced APIs anyway.

Yes, keep as is for now.