frost-core v1.0.0-rc.0

• The frost-core::frost module contents were merged into frost-core, thus
  eliminating the frost module. You can adapt any calling code with e.g.
  changing use frost_core::frost::* to use frost-core::*.
• Challenge, BindingFactor, BindingFactorList and GroupCommitment
  are no longer public (you can use them with the internals feature).
• Both serde serialization and the default byte-oriented serialization now
  include a version field (a u8) at the beginning which is always 0 for now. The
  ciphersuite ID field was moved from the last field to the second field, after
  the version. Both version and ciphersuite ID are now grouped into a "header"
  struct, which affects self-describing formats like JSON. The ciphersuite ID
  string was also changed for all ciphersuites: it is now equal to the
  contextString of each ciphersuite per the FROST spec.
• Add an option to disable cheater detection during aggregation of signatures.
• Add PublicKeyPackage::from_commitment() and
  PublicKeyPackage::from_dkg_commitments to create a PublicKeyPackage from
  the commitments generated in trusted dealer or distributed key generation.
• Ciphersuite crates now re-export serde if enabled.
• Convert all HashMaps to BTreeMaps.
• Update some field names in KeyPackage, Package, SecretShare and PublicKeyPackage.
• Add generate Randomizer by hashing SigningPackage
• Add postcard-serde-encoded serialization as the default
• Remove BindingFactor::deserialize() and BindingFactorList::iter()