EOF validation in tools / tests

[chfast]

When an execution code is taken from external source (e.g. CLI or JSON tests) we should perform EOF validation to keep the EOF guarantee of deployed code being always valid.

Places where it's needed:

• CLI EVM execution (evmc run?)
• JSON state test loader or runner statetest: Validate EOF containers in test state #593

[gumb0]

JSON tests should validate it before being filled, not sure we need to do it another time for them.

[chfast]

JSON tests should validate it before being filled, not sure we need to do it another time for them.

This is just sanity check to detect broken tests. Otherwise you will see some crashes.

[pdobacz]

Is this still relevant? Also, to what extent exactly does #593 satisfy "JSON state test loader or runner"? (checkbox is not ticked yet)