As a user of POMBA, I want rules that take advantage of SDC data, across the currently supported resources and fields. 

SDC fields come in two flavours, which require different handling in the rules

• Meta data
  • These fields describe the instantiation of this field in other contexts
  • These are unsuitable for attribute comparison, but rather define their own restrictions that could be used as the source of the rule, or "source of truth"
• Data
  • These are instance values that can directly be compared to values coming from other contexts