paths: use /usr/local/caesure/
BlockDB.scan_block_chain: use BLOCK.unpack (header_only=True)
BlockDB.add: comment on stealth forks.
ledger: talk about the road taken.
sprinkle some 'bytes' types in signatures.
BLOCK.unpack: header_only option.
unpack_headers: unpack the reply to a 'getheaders'.
fix a bug in the AA tree delete code.

outpoint_set.get_output: fetch a particular output (without popping it).
tree_remove: when deleting a leaf node, check whether to link left or right child.
tree_size: compute the size of the tree manually.
UTXO_Map:
  compute_length: use tree_size.
  get_utxo: get an output without popping it.
  __iter__: don't iter over nodes, you dolt.
  dump: don't mangle txnames.
UTXO_Scan_Map:
  more detail in comment.
  add __contains__.
reworking toward multi-universe design.

RecentBlocks: a class to hold all recent ledgers back to the chosen horizon.
LedgerState:
  one of these for each live tip.
  save_state, load_state: use asn1 for disk cache.
  feed_block: use enumerate
catch_up:
  pulled out of LedgerState.
  get_names: return empty list when no blockchain.
  hold back by 20 blocks, then feed one at a time after scan/reload.
redesigned block hoover.

per Pieter Wuille: use getheaders rather than getblocks to download the block names.
  [iterative getblocks was just too flaky, this seems much more reliable]
connection.getheaders: use getheaders to fetch from N..tip.
gitignore
emacs~
cython outputs.