Merge pull request #8 from apanda/master

Mostly: Make the instrumenter less chatty, it is now reasonably stable, let's not print out lots of stuff
Merge pull request #9 from apanda/master

Kind of incomplete replay scheduler
Merge pull request #10 from apanda/master

Fix the problem with the missing first event
Merge pull request #11 from apanda/master

Checkpointing things from today.
Merge remote-tracking branch 'upstream/master' into HEAD