Most of these methods did not contain all the relevant information
inside the object and were not using a similar formatting type.
Moreover, the existence of a suboptimal String method breaks usage
with more advanced data dumping tools like go-spew.
This significantly reduces the dependency closure of ethclient, which no
longer depends on core/vm as of this change.
All uses of vm.Logs are replaced by []*types.Log. NewLog is gone too,
the constructor simply returned a literal.