Merge pull request #1816

b867e40 CreateNewBlock: Stick height in coinbase so we pass template sanity check (Luke Dashjr)
60755db submitblock: Check for duplicate submissions explicitly (Luke Dashjr)
bc6cb41 QA RPC tests: Add tests block block proposals (Luke Dashjr)
9765a50 Implement BIP 23 Block Proposal (Luke Dashjr)
3dcbb9b Abstract DecodeHexBlk and BIP22ValidationResult functions out of submitblock (Luke Dashjr)
132ea9b miner_tests: Disable checkpoints so they don't fail the subsidy-change test (Luke Dashjr)
df08a62 TestBlockValidity function for CBlock proposals (used by CreateNewBlock) (Luke Dashjr)
4ea1be7 CreateNewBlock and miner_tests: Also check generated template is valid by CheckBlockHeader, ContextualCheckBlockHeader, CheckBlock, and ContextualCheckBlock (Luke Dashjr)
a48f2d6 Abstract context-dependent block checking from acceptance (Luke Dashjr)