Ability to turn off ALL validation for high-speed (release configuration) emission

[n8allan]

Some validation checks can currently be omitted, but others runs regardless. For scenarios where compile-time is important (dynamic or JIT), all of the debug features should be able to be omitted.

Implementation options:

1. extend the places that check for the current flag;
2. introduce an alternative internal implementation that is switched to to avoid all the branches;