message: add comments describing the purpose of these new objects
diff: @@ -47,7 +47,11 @@ static boost::atomic<bool> fIsChainNearlySyncd(false);
  extern CTweakRef<uint64_t> miningBlockSize;
  extern CTweakRef<unsigned int> ebTweak;
  -extern CCriticalSection cs_previousblock;
  +extern CCriticalSection cs_previousblock; // Protects the vPreviousBlock array
  +// This vector holds hashes of the transactions in the previous block. When a new block comes in it is used to
  +// flush the orphan pool of any transactions that may have trickled in AFTER the block that mines them has already
  +// been processed. In this case a transaction may look like an orphan because its parents have already been removed
  +// from the UTXO set.
  vector<uint256> vPreviousBlock;
  bool IsTrafficShapingEnabled();
  