Coinbase arbitrary (#1219)

Coinbase arbitrary (#1219)

* get mining address

* Set mining addr

* go fmt

* Fix CI

* Avoid mining to null addr

* Prevent mining to null addr for api

* clean vendor

* format get/setMiningAddress func

* Update if statements format

* Combine

* go fmt

* clean GetMiningAddress()

* compact IF statements

* compact IF statements

* revert

* SetMiningAddress for non-local address

* combine

* go fmt

* private getProgramByAddress()

* Avoid mining to nil addr for get-work

* Roll back

* Fix CI

* tweak func seq

* Add /get-coinbase-arbitrary api

* setCoinbaseArbitrary

* abHexStr

* re-construct code

* go fmt

* fix conflict

* go fmt

* re org code

* GetBlockTemplate

* rm get-coinbase-arbitrary

* go fmt

* RenewBlkTplWithArbitrary

* clean up

* CoinbaseArbitraryOversize check

* Iter to find CoinbaseArbitrary

* go fmt

* Change arbitrary json from string to chainjson

* Fix CI

* get/set-coinbase-arbitrary

* Fix

* go fmt

* Fix

* Fix

* Fix CI

* Disable test -v

* Fix coinbase arbitrary in get-work-json

* Fix arbitrary call

* Roll back (Ignore coinbase arbitrary in get-work-json)

* Rm block.CoinbaseArbitrary()

* Reformat

* Clean getBlockHelper()

* Add import

* Fix getBlockHelper() logic

* Clean up codes