How to handle the "all", "one_or_more", "zero_or_more", "exactly_one", and "zero_or_one"
meta-member keywords?

Technically, they are allowed at any level where a field name would be allowed in JSON. However, we currently only support them in the following places:

• We currently support "all", "one_or_more" and "zero_or_more" directly under
  "flow_mod_types" because that is all that was illustrated.
• We currently support "exactly_one" and "zero_or_one" directly under "match_set" and
  "instruction_set" because that was all that was illustrated.
• We currently support "exactly_one" and "zero_or_one" for action lists, i.e., actions in
  instructions_set, action_set in bucket_type, and actions in packet_out
• In all the above cases, I believe we accept JSON which would not be a valid TTP and
  might need to add extra validation. This is true elsewhere as well.

These are the examples of where each is actually used in the SPEC:

• "all" is only used in one example under "flow_mod_types" in the middle of page 43
• "one_or_more" is never illustrated with an example
• "zero_or_more" sometimes points to an object and sometimes to an array. It seems like it
  should always do one or the other. Only used under "flow_mod_types" in the
  example.
• "exactly_one" examples for "instruction_set" and "match_set"
• "zero_or_one" is only used in "instruction_set" and only to point to a single object;
  never to an array. It seems like it should always point to an array, even
  if it is an array with a single element.