Enforce that coinbases must be protected
This PR forces miners to place their funds in the private value transfer system, making "transparent coins" opt-in for users, and increasing privacy for all participants on a systemic level.
Closes#101.
Signing pours with ed25519
This is an alternative to #964 which uses ed25519 instead of secp256k1, and avoids the separate hash for fitting the public key into the `h_sig` block. It's based on @defuse's work in that branch.
Closes#808.
All blocks before the first subsidy halving block, with the exception of
the genesis block, must contain an output which sends 20% of the block
subsidy value to a scriptPubKey `FOUNDERS_REWARD_SCRIPT`.
The main and test networks are configured to use parameters that are currently
low-memory but usable with the basic solver; they will be increased once the
solver is optimised. The regtest network is configured to have extremely low
memory usage for speed.
Note that Bitcoin's double-hasher is used for the difficulty check. This does
not match the paper, but is simpler than changing the block header
serialization. Single hashing is kept for the EquiHash solver because there is
no requirement on execution time there, only on memory usage.
Some specifics on consensus changes:
* Transactions must be anchored to a real anchor in the chain.
* Anchors are pushed and popped during ConnectBlock/DisconnectBlock as appropriate.
* DisconnectTip triggers evictions, under some circumstances, of transactions in the
mempool which are anchored to roots that are no longer valid.
* Commitments append to the tree at the current best root during ConnectBlock.
* PourTxs cannot appear in coinbase transactions.
* Transactions can only contain empty vin/vouts if they contain a PourTx.
* PourTx public values must be well-formed (not negative or too large).
* Transactions cannot have the same serial twice throughout all PourTxs.
