Improve support for start-many

- refactored CActiveMasternode
- added masternodeconfig to handle remote masternode configuration
- read masternodeconfig upon init
- new masternode rpc commands: stop-many, start-alias, stop-alias, list-conf
- added notCapableReason field for better handling not capable issues
This is selecting the last 1000DRK input instead of the one specified for start-alias. I'm guessing this was for debugging purposes. It should be matching TXID and OutputIndex, then only sending the match back.