* Change cast_list_to_dict to more generic rekey_on_member
cast_list_to_dict was taking an arbitrary data format in and returning
an arbitrary data format out. Rework this to be a more generic function
which creates a dict of dicts based on a member of the dict.
Remove cast_dict_to_list since rekey_on_member handles the use cases we
know about and cast_dict_to_list suffers from the same problems as
cast_list_to_dict. If this is still needed we could think about filters
we could add to do this in a short jinja2 pipeline.
* Fix bare excepts (bare excepts even catch sys.exit())