Expectation log statement now puts current before last.
Removed post-contraction hook.
Added beginning run debug log statement.
Moved contraction to occur between the first and second iterations.
Cosmetic:  Fixed spelling mistake in fold name
Added more debug log statements in policies.
Added __iadd__ method to the 2D System class.
Fixed the stupid 1D/2D inconsistency in the state center data field name.