delete debugging printout
alphabatize menu returned by basic_level_variable.varoptions
Support auxiliary parameters (associated with variable and diag set)
and look at them for the temporary jerry_potter diag set.
When computing a derived variable, check that we have all the prerequites.
If a derived variable depends on another derived variable, pospone its
computation until it can be computed.  If we get more complicated
dependencies we'll probably have to change this to use a queuing systme
or otherwise analyzing the dependency graph.