FAHCore 22 v0.0.13 and Checkpoint frequency

[bruce]

I do like the adjustability of the CPU core, but the FAHCore can only write a checkpoint when certain aspects of the analysis are synchronized. I don't know what it costs the CPUs to synchronize so often or what it would cost to perform those extra steps in the GPU core. You certainly don't want a checkpoint that's corrupt because part of it was written a time=T and another part of it was written at a different time.