* core,eth: add empty tx logger hooks

* core,eth: add initial and remaining gas to tx hooks

* store tx gasLimit in js tracer

* use gasLimit to compute intrinsic cost for js tracer

* re-use rules in transitiondb

* rm logs

* rm logs

* Mv some fields from Start to TxStart

* simplify sender lookup in prestate tracer

* mv env to TxStart

* Revert "mv env to TxStart"

This reverts commit 656939634b9aff19f55a1cd167345faf8b1ec310.

* Revert "simplify sender lookup in prestate tracer"

This reverts commit ab65bce48007cab99e68232e7aac2fe008338d50.

* Revert "Mv some fields from Start to TxStart"

This reverts commit aa50d3d9b2559addc80df966111ef5fb5d0c1b6b.

* fix intrinsic gas for prestate tracer

* add comments

* refactor

* fix test case

* simplify consumedGas calc in prestate tracer