Add support for augmented eosio.msig::approve action with proposal_hash in cleos

[conr2d]

Change Description

Fixes #6272.
Following changes are applied:

• cleos multisig review shows the ID of proposed transaction.
• cleos multisig approve accepts a hash of proposed transaction to check whether the proposed transaction is identical to the one to be approved.

[arhag]

@conr2d:

Thank you for your contribution. We appreciate all of the great work you have been doing lately with PRs and hope you keep it up.

I had some plans with the cleos multisig command that I didn't properly document in the GitHub issues. These touched on the changes that you have implemented here to resolve #6272. It worked out easier and cleaner to just submit PR #6356 with its existing commits than to merge in your branch in with my changes and resolve some of the conflicts including making some style changes (renaming trx_id to be more verbose and the changing the description of proposal_hash). So PR #6356 will simply supersede this PR.

However, we want to give you credit for your work here. So, we have shoutout to you thats links back here which was added to the description of PR #6356.