Loggers

[brandondube]

Related to #12

Logging information, and/or live updates should also be made easy to do. Maybe betakicker takes a callback to push state to on every iteration; that callback can do all sorts of stuff; save to memory, to disk, update a plot, and so on. We could define a suite of standard callbacks, too (this should be a standard issue). That opens us to make standard dashboards, too, but that seems like it's probably doable. Maybe we could make a fancy web GUI that way N people could watch EFC progress at the same time.