* `usedBytes` was not named appropriately. it indicates the last
populated position in the data (the last valid index) for slicing
purposes (i.e. the position is passed to `toOpenArray`)
* Fixed the `==` operator for DBKeys
* Use one-byte key for the 'canonical head hash'
* Move and cleanup interpreter files - prepare for redesign of VM
* fix call comment aobut recursive dependencies
* memory: use a template again and avoid (?) a cstring-> string conversion
* Fix stack test regression
* Fix recursive dependency on logging_ops, test_vm_json compiles but regression :/
* Fix signextend regression
* Fix 3 signed test and sha3 test
* Decoupling op logic and gas - introduce gasometer, rework opcode declaration
* Remove gas constants for gas opcode computation
* Remove gas constants for precompiled contracts
* make vm_types compile
* Make opcode, call and computation compile
* Distinguish between dynamic and complex gas costs, fix arithmetic
* Fix context and sha3
* update memory and storage ops
* Log opcode uses memory expansion code
* update/stub system_ops with gas costs
* Make test compile. Deactivate stub test_vm
* all tests compiles, opcode fails due to https://github.com/nim-lang/Nim/issues/8007 (const object variant in tables reset at runtime)
* Create an enum without holes - workaround: https://github.com/nim-lang/Nim/issues/8007
* Use arrays instead of tables for GasCosts, remove some unused imports - passing all basic tests!
* Make test_vm_json compile
* Fix test_vm_json - workaround https://github.com/nim-lang/Nim/issues/8015
* fix memory expansion cost bug
* Remove leftover special handling from before GckMemExpansion
* cleanup outdated comment, better align =
* Fix sha3 gas cost not taking memory expansion into account
* Improve gas error reporting of test_vm_json
* Fix gas computation regression due to mem expansion
* mass replace for memExpansion->RequestedMemSize was too eager
* fix log gas cost (no tests :/)
* missed a static FeeSchedule
* static as expression is fickle
Zahary Karadjov
Yuriy Glukhov
Mamy Ratsimbazafy