Age

TODO -- discuss what the appropriate way is to represent the age of mouse models. For a lot of human data, we have used ISO8601 duration or time intervals ( e.g. P40Y10M05D), but this may not be what we want here. I am making the following suggestions

Data model

Field	Type	Multiplicity	Description
years	int32	1..1	Number of years. REQUIRED (may be zero).
weeks	int32	1..1	Number of weeks. REQUIRED (may be zero).
days	int32	1..1	Number of days. REQUIRED (may be zero).

AgeRange

Some of the age data is provided as ranges, e.g., "ageweeks": "7-9wks"

Data model

Field	Type	Multiplicity	Description
start	Age	1..1	An Age message
end	Age	1..1	An Age message

Example

For instance, to represent the "7-9wks", one could use an AgeRange object as follows..

ageRange:
  start:
      years: 0
      weeks: 7
      days: 0
  end:
      years: 0
      weeks: 9
      days: 0