Initial commit of jep-8
Incorporate review feedback

Also added a rationale section that covers the alternatives
considered and why they were not chosen.
Add exptype to the proposals index
Marking JEP-8 as accepted
Merge branch 'spec-jep-8' into develop

* spec-jep-8:
  Marking JEP-8 as accepted
  Add exptype to the proposals index
  Incorporate review feedback
  Initial commit of jep-8