b4e4ba4 Introduce convenience type CTransactionRef (Pieter Wuille)
1662b43 Make CBlock::vtx a vector of shared_ptr<CTransaction> (Pieter Wuille)
da60506 Add deserializing constructors to CTransaction and CMutableTransaction (Pieter Wuille)
0e85204 Add serialization for unique_ptr and shared_ptr (Pieter Wuille)
This switches the Merkle tree logic for blocks to one that runs in constant (small) space.
The old code is moved to tests, and a new test is added that for various combinations of
block sizes, transaction positions to compute a branch for, and mutations:
* Verifies that the old code and new code agree for the Merkle root.
* Verifies that the old code and new code agree for the Merkle branch.
* Verifies that the computed Merkle branch is valid.
* Verifies that mutations don't change the Merkle root.
* Verifies that mutations are correctly detected.
