Reduced AT state info from per-AT address + state hash + fees to AT count + total AT fees + hash of all AT states.
Modified Block and Controller to support above. Controller needs more work regarding CachedBlockMessages.
Note that blocks fetched from archive are in old V1 format.
Changed Triple<BlockData, List<TransactionData>, List<ATStateData>> to BlockTransformation to support both V1 and V2 forms.
Set min peer version to 3.3.203 in BlockV2Message class.
This allows for compatibility with TRANSFER_PRIVS validation in commit 8950bb7, which treats any account with a non-null reference as "existing". It also avoids possible unknown side effects from trying to process and store transactions with a null reference - something that wouldn't have been possible until the validation was removed.
This should prevent the failed transactions that are encountered when issuing two or more in a short space of time. Using a feature trigger (hard fork) to release this, to avoid potential consensus confusion around the time of the update (older versions could consider the main chain invalid until updating).
Currently, new transactions take a very long time to be included in each block (or reach the intended recipient), because each node has to obtain a repository lock and import the transaction before it notifies its peers. This can take a long time due to the lock being held by the block minter or synchronizer, and this compounds with every peer that the transaction is routed through.
Validating signatures doesn't require a lock, and so can take place very soon after receipt of a new transaction. This change causes each node to broadcast a new transaction to its peers as soon as its signature is validated, rather than waiting until after the import.
When a notified peer then makes a request for the transaction data itself, this can now be loaded from the sig-valid import queue as an alternative to the repository (since they won't be in the repository until after the import, which likely won't have happened yet).
One small downside to this approach is that each unconfirmed transaction is now notified twice - once after the signature is deemed valid, and again in Controller.onNewTransaction(), but this should be an acceptable trade off given the speed improvements it should achieve. Another downside is that it could cause invalid transactions (with valid signatures) to propagate, but these would quickly be added to each peer's invalidUnconfirmedTransactions list after the import failure, and therefore be ignored.
Importing has to be single threaded since it requires the database lock, but there's nothing to stop us from validating signatures on multiple threads, as no lock is required. So it makes sense to separate these two functions to allow for possible multi threaded signature validation in the future, to speed up the process.
Everything remains single threaded in this commit. It should be functionally the same as before, to reduce risk.
