Update roadmap based on discussion at contributor meetup.
Add stack of previous values to converter
produce more readable error messages
refactor to hide structs behind an interface
Use EXIT pseudo-signal
Merge pull request #2806 from ddysher/exit-integration

Use EXIT pseudo-signal
Merge pull request #2765 from lavalamp/conv

conversion refactoring
Merge pull request #2784 from bgrant0607/docfix

Update roadmap based on discussion at contributor meetup.