Proved ord_isoI, ord_iso_refl. Simplified proof of ord_iso_restrict_pred. Proved theorems irrefl_0, ..., well_ord_0.

Proved cadd_cmult_distrib.

Now proof of Ord_jump_cardinal uses ordertype_pred_unfold; proof of sum_0_eqpoll uses bij_0_sum; proof of sum_0_eqpoll uses sum_prod_distrib_bij; proof of sum_assoc_eqpoll uses sum_assoc_bij; proof of prod_assoc_eqpoll uses prod_assoc_bij. Proved well_ord_cadd_cmult_distrib.