0.7.9.48:

0.7.9.48:
	Fix COMPUTE-SLOTS :AROUND to do predictable things on
		STANDARD-CLASS
	... put a new slot (ALLOCATION-CLASS) into slotds, to be
		initialized to the relevant class if the allocation of
		the slot is :CLASS
	... use SLOT-ALLOCATION-CLASS where SLOT-ALLOCATION was used in
		the case of a :CLASS allocation
	... divide the COMPUTE-SLOTS :AROUND method into two, and leave
		the FUNCALLABLE-INSTANCE one alone