Add spec suites for stateful refs (atoms/volatiles/delays/promises), multimethods
(dispatch + hierarchies), and protocols/types/records. Bugs caught and fixed:
- reify with multiple methods registered only the first (stepped i by 2 over
one-element specs); now collects every method spec
- get-method/methods/remove-method evaluated their arg to the dispatch fn, but a
multimethod's methods live on its var — now resolve the var (get-method and
methods are special forms; remove-method fixed). get-method/methods added.
- no global hierarchy: 2-arg derive modified a throwaway, isa? was hardcoded
false, parents missing, ancestors/descendants returned arrays (so contains?
failed), and dispatch ignored derive. Now a global hierarchy backs the 1/2-arg
derive/isa?/parents/ancestors/descendants (returning sets) and multimethod
dispatch falls back to it.
Corrected a phase5 port assertion that encoded the old isa? bug.
conformance 218/218, jpm test green.
