feat!: enable no_std support for tari_crypto

[SWvheerden]

This PR adds in no_std support for TariCrypto. The following changes where made to enable this:

• thiserror was swapped out for Snafu as thiserror does not support no_std while snafu does.
• use std:: was changed to use core::
• make all dependencies default-features = false
• make BulletProofPlus an optional feature
• make serde an optional feature
• Make precomputed_tables optional as they require large internal memory
• remove lazy_static as a dependency (replaced by one-cell)
• changed sign message to use supplied RNG, and not thread_local internally