This blindly changes logging to nim-chronicles - issues that ensue:
* keeps gas cost computation logs hidden behind flag
* unclear if logScope is practical - for example, since vm is split over
many files, topics get lost when using simple top-level per-module
topics
* when passing named object around, scope should incliude the name of
the object but this is caught neither by logScope nor by dynamicLogScope
* 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
Jacek Sieka
Mamy Ratsimbazafy
Yuriy Glukhov