Description

Initial implementation of the WASM module package signing. Added some basic structures and objects needed for package signing.

Related Issue(s)

replaced cryptoxide crate usage with RustCrypto crates
added module sign cli command
added Blake2b256 hashing object
added ed25519 public and private keys objects with decoding from PEM format implementation
added x.509 certificate object with decoding from PEM format implementation
refactored some stuff