TLog Notes

ququeCommittingVersion is set the first time the TLog attempts to do commit to the disk queue. If we shutdown while that is still 0 it means we never attempted a disk queue commit. In this case, set the queueCommittedVersion to the maximum possible version so that anyone waiting on whenAtLeast() for that asyncVar will be notified that it will never complete. so all locations which are waiting on whenAtLeast now check if the value is equal to the maximum value and return when that is the case since the disk queue did not actually commit