implement elems as call to MVM_repr_elems
atpos_i is another hot op (implemented through MVM_repr_at_pos_i)
push_i is next, unshift_i can have the very same code.
implement iter, iterkey_s and iterval
implement bindpos_o and bindkey_o
shift_i and pop_i are very simple
getattr_i and eqat_s
existskey is another common op.
implement unbox_[ins]
Merge branch 'moar-jit' into HEAD
Correct an arg count.
Merge branch 'moar-jit' into jit-moar-ops
support bindattr_inso
implement all the getattr ops: inso.
implement newlexotic
setelemspos for le jit
iter, iterval and iterkey make stuff hang in compilation :(
istype is invokish and its return value ought to be INT, not VOID

so i just comment it out for the time being.
support for bindpos_i is trivial to add
add isint/isnum/isstr/islist/ishash

in the interest of finding out what other ops will cause
bails down the road. These ops ought to be implemented
by generating a tiny bit of assembly code instead of a
C call, but i leave that for brrt++ to do.