New gas estimation algorithm (trufflesuite#435)

* WIP, testing code

* WIP testing code

* WIP new algorithm

* WIP disregard

* WIP  fix logic, not final

* WIP fix summation algo, not final

* WIP improve gas accounting

* WIP not stable

* WIP - fixed base summation bug

* WIP Tests running; SVT -> WIP

* Rename gasLimit

* WIP; composite context fix

* Remove testing code from blockchain_double

* Fix deployment costs, recognize EIP150 opcodes

* SVT

May not be necessary anymore

* Cleanup gas estimation, remove old code

* FIX SVT - STABLE

* Minor cleanup

* Finalize gas estimation

Cleanup all unneccessary code.

* Fix SVT amount withheld

* Increase recursive DELEGATECALL depth

* Fix SVT

* Fix bug in SVT calculation

* Cleanup gasEstimation

* Fix gas estimation, small refactor