Generated message types should implement MessageWithConstraints

[alexander-yevsyukov]

... at least for backward compatibility with the code from core-java.

[alexander-yevsyukov]

@armiol, it would partially solve the issue with ”required” INT fields we have in core-java.

If we do this, the checking of command messages would just call validate() once again.

[armiol]

We have discussed that with @dmdashenkov several weeks ago.

What I proposed is to omit this interface for now, since there is no code which ever uses this interface at runtime.

[armiol]

Let's discuss this issue vocally tomorrow.