Fix #220: Correct runtime return type for boolean & and | ops
Fix #218: class literal for existential value classes.
Merge pull request #244 from gzm0/nonlazy-boolean-op

Fix #220: Correct runtime return type for boolean & and | ops
Merge pull request #245 from sjrd/valueclasses-classtag-existential

Fix #218: class literal for existential value classes.