* Ethereum Classic Monetary Policy
Create a new parameter `ecip1017EraRounds`. When the block number
passes one era rounds, the reward is reduced by 20%.
See https://github.com/ethereumproject/ECIPs/blob/master/ECIPs/ECIP-1017.md
* Update rewards for uncle miners for ECIP1017
In the monetary policy, the rewards are changed from "up to 7/8 of the
reward" to "1/32 of the reward".
* Fix an off-by-one error in ECIP1017 era calculation
According to
https://github.com/ethereumproject/ECIPs/blob/master/ECIPs/ECIP-1017.md,
when in block number 5,000,000, it should still be in Era 1 (which in
our code `era == 0`). So we need to check whether the `rem` equals to
zero and act accordingly when calculating the era.
* `ecip1017_era_rounds` missing from EthashParams when run in build bot
* strip out ecip1017_eras_block_reward function and add unit test
* add a simple test for is_push so that every small utility has a corresponding unit test
* split evm/factory.rs into two files as the TODO suggests
* style fixes according to review comments
* header back-references for on demand
* initial back-reference implementation for on demand requests
* answer requests from cache
* answer requests from cache, add tests
* strongly typed responses for vectors of homogeneous requests
* fix fallout in RPC without optimizing
* Adding CLI option for port shift and unsafe expose.
* Fixing IPC path.
* Fix hosts when attempting to expose on all interfaces.
* Fixing test.
* Fix typo.
* move native_contracts ABIs to JSON files, add urlhint
* port hash-fetch to futures, fix tests
* fix dapps compilation, defer async port to later
* activate dapps server in the light client
* better formatting
* separate modules for consensus snapshot chunks
* bulk of authority warp logic
* finish authority warp implementation
* squash warnings and enable authority snapshot mode
* test harness for PoA
* fiddle with harness
* epoch generation proof fixes
* update constructor code
* store epoch transition proof after block commit
* basic snap and restore test
* use keyvaluedb in state restoration
* decompress chunks
* fix encoding issues
* fixed-to-contract-to-contract test
* implement ancient block import
* restore genesis transition in PoW snapshot
* add format version method to snapshot components
* supported version numbers in snapshot_components
* allow returning of ancient epoch transitions
* genesis hash mismatch check
* remove commented code
