Upgrade iotex-antenna-go

Support the hard fork in iotex-api.

Full Changelog: v0.3.5...v0.3.6

Upgrade dependences and add agent contract support

Upgrade dependencies, especially go-ethereum package. Add agent contract support for vote sync component

v0.3.4: - upgrade iotex-proto and iotex-antenna-go (#151)

- change to use api.iotex.one candidate indexer instead of analytics candidate indexer

v0.3.2: still run update voting powers even when nothing to sync (#149)

* still run update voting powers even when nothing to sync

* also include go mod update for go 1.14

v0.2.18

No need to fetch more blocks once ec.archive.TipHeight passed ec.ceil…

Stop pulling Ethereum after the ceiling height

Add a ceiling height that allows the service to stop pulling Ethereum once it reaches this height

Reduce Update Voting Power Size

Reduce Update Voting Power Size (#143)

* enlarge gas limit

* reduce update voting power size

Enlarge Gas Limit

increase from 5000000 to 7000000

Introduce native staking committee

Add a new server and also include the native staking committee result into vote sync

set dardanellesHeight

votesync compatible with dardanelles 5s block interval