v0.24.0

Added

• GPGSigner to support gpg signing via Signer interface (#341, #419)

Changed

• Use max salt lengths in RSA PSS signature creation & automatically verify previous/new
  sigs (#422)
• Speed up canonical json encoding (#410)
• Bumped dependencies: cffi (#415), colorama (#413), cryptography (#405, #406, #414,
  #417, #424, #425), ed25519 (#412)
• Changed Debian packaging metadata (#392)

Fixed

• Minor test fixes (#403, #420)