Add dummy bitcoin.core.key.CPubKey class
Add CBitcoinAddressError exception
Merge commit '5a0380a9cb83cb2960d9f440174828b831ad4e4e'
Merge commit '6d5758a36fecf71c89d7486aafdb2ac521100185'
Fix up CBase58Data initialization so subclasses can use __init__()
Merge commit '675ea5715f99e83a7d62e4ff6326d4766bc6700d'