Formatting fix.
Add pubkey_hash_prefix, script_hash_prefix, and secret_prefix base58 parameters to chain descriptions.
Remove namecoin parameters since namecoin isn't really supported, or planned to be supported.
Drop output_ prefix from hash and index of Input type.
Fix broken code - passing self makes the two cases asymmetrical.
Allow either a integer value or standard Python date time for the Block.time value.
Formatting improvements.
OP_0 shouldn't be treated like the other data pushing opcodes since it is a single-byte instruction.
Restructure Script class to be a binary string instead of a tuple. This allows Script to be used to encode non-parseable strings, such as some coinbases, and is generally a cleaner design.

NOTE: This breaks compatibility with the previous Script API.
Allow serialize_list to default to class-based serialization (calling the serialize() method for each element).
Use a recordtype for signatures instead of deriving from tuple directly. This is both cleaner, and more expressive.

Also, add SerializableMixin so that signatures may be encoded/decoded like other types.
Remove 'Outputs' from the names of the index structures, to make it a little less verbose.
Add 'repr' for ContractOutPoint, as the default  would print binary data to the prompt.
Rewrite PatriciaLink to have both a node and hash value (using the typical HashableMixin, although the hash is actually just cached from the node). This enables backends which lookup by hash or by node, and saving of the cached hash value when constructing new links.
Release v0.0.6
Version bump for development.