Comments from Dan (#2): deeply re-work on the following properties

action (#18)
activityDuration
activityFrequency

for non-health activities, actions and events too?

• affectedBy, availableIn, cost, warning, ....

very broad wording. health only or more broadly applicable?
*birthPlace

vs. general / core treatment of people? (revisit family tree stalled work?)

calories
cookingMethod
cookTime

recipes stay in core? see #17

code
*always was v general, should we generalize it beyond health for core?
*we also have an related type spelled http://schema.org/Code

Closed!
To be continued here: schemaorg/schemaorg#1116