Here is a brief list of things that still need to be done.

API:
   - Reorganize the package layout to be more modular.
   - Support multiple active wallets.

Protocol:
   - Start up faster
      - Store a block locator in the persisted chain
      - Use the getheaders command to speed up the initial chain download
   - Implement tx fees.
   - Longer term potentially add a getmerklebranch protocol command so we can check 0-confirmation transactions.

Examples/documentation:
   - Implement a simple Swing GUI payment app.

Cleanup:
   - Find a way to avoid some horrid hacks when shutting down the network connection.
   - Implement a BitCoin class that encapsulates a BigInteger and formatting.
   - Make NetworkParameters use subclasses instead of static methods to construct.

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Impacts from Steves changes:
- LazyParseByteCacheTest:
   - some redundant asserts
   - huge functions

- Delete the code related to deduping. The new network management code to be checked in later makes it unnecessary.
  Also remove singleDigest as a result (it duplicates Sha256Hash).
- More thoroughly review UnsafeByteArrayOutputStream