Changes for Sidechains Integration Step 2

[ptagl]

This pull request brings the following changes:

• Added a check for sidechain creation outputs to be sure that the configuration of the bitvectors is consistent; in particular, the size of the bitvector must be such that it can be mapped to a Merkle tree, having a number of leaves that is a power of two. #131
• Added the SidechainId as a public input for the certificate proofs. #134
• The public input constant for certificate proofs has been made optional. #143
• Updated Rust dependencies to address vulnerabilities. #139
• Added a new RPC command for miners to compute and retrieve the root of the transactions Merkle tree and of the Sidechain Transaction Commitment tree. #121
• Fixed the undo database to avoid incompatibility issues between Zend and Zendoo (after the introduction of sidechains). #145
• Fixed the mining of blocks so that the field hashScTxsCommitment is kept empty until the introduction of sidechains support. #144
• Fixed some code that could eventually cause a crash when Zendoo was run with the -disablewallet flag. #141
• Improved the management of proofs by keeping track of the list of failed ones as a return value of the Rust verification interface. #130
• Fixed both the implementation and documentation/help of the send_certificate RCP command. #116
• Added a function
• Backport Zend 2.0.22
• Backport Zend 2.0.23

[cronicc]

@ptagl I'd ideally like for https://github.com/HorizenOfficial/zend_oo/pull/148 to get reviewed and merged before we merge this PR. If it gets included we can re-enable CI for everyone.