* cannon: Track steps between ll and sc

* cannon: Track rmw failures, keep counts for rmw ops

* cannon: Add unit tests for stats tracking

* cannon: Simplify step count stats

* cannon: Track explicit memory reservation invalidation

* cannon: Set stats on DebugInfo

* cannon: Rename method

* cannon: Track forced preemptions

* cannon: Track failed wakeup traversals

* cannon: Track idle steps for thread 0

* cannon: Reorganize vm metrics, add methods to record new stats

* cannon: Use uint64 over int

* cannon: Record new metrics

* cannon: Update readme run-trace flag

* cannon: Use uint64 type consistently

* cannon: Add debugInfo serialization test

* cannon: Check metrics in executor test

* cannon: Record total steps

* cannon: Check error in test

* cannon: Enable stats tracking via --debug-info flag

* cannon: Fix steps json field name

* cannon: Keep a small cache of ll steps for more accurate tracking

* cannon: Tweak test

* cannon: Modify test to better validate json parsing

* cannon: Use non-threadsafe simplelru