Validate the interpreter's major version against the contract's/library's major version

[jjcnn]

It looks like we don't always check that the contract/library has a major version that matches the major version of the checker/interpreter. At least this is the case when a message is sent to a library (see #1175).

This is not a problem as long as there is only a single major version in play, but should be checked thoroughly once we reach v1.