Fix bug #364: Add a specific cost analysis for nondet disjunctions.

This bug was caused because we assumed that all disjunctions that the cost
analysis examined were semidet disjunctions.  This patch adds a separate
predicate to calculate the cost of nondet disjunctions, it simply sums up
the costs of the disjuncts.

deep_profiler/autopar_costs.m:
    As above.

deep_profiler/autopar_search_goals.m
    Conform to above changes.

deep_profiler/autopar_search_callgraph.m:
    When the auto-parallelisation analysis of a procedure throws an
    exception print out the identity of the procedure.

NEWS:
    Add news item.