Trivial Description
We have some aliases in opid_util.h/cc called MinimumOpId() and InvalidOpId() that are poorly named. We should consider changing InvalidOpId() to (0,0) and MinimumOpId() to (1,0) or something similar to reflect how we use those values today. Or come up with better naming. The actual, operational minimum OpId that can appear in a WAL is (1,1).