Auxpow implementation
Auxpow: release reference to CReserveKey
Auxpow: blockdb upgrade message, chain ID method replaced with const
Fixes to auxpow RPC
Fix to auxpow blockversion check
Tweaks to auxpow RPC, remove unused CReserveKey reference
Require reindex of pre-auxpow database, fix mis-requiring reindex of empty DB
Merge branch 'auxpow' merged mining

This merge enables merged mining on testnet