MemLog.v: checkpoint progress on tp_atomicity
MemLog.v: checkpoint progress on tp_atomicity

a good way there, except for TCommit / TBegin, which require
iterating over the log contents and thus probably some extra
induction..

mit-pdos/fscq-impl,mit-pdos/fscq-impl,mit-pdos/fscq-impl,mit-pdos/fscq-impl,mit-pdos/fscq-impl