Each post should go through these edit passes:
1. STYLE -- Editor and write work together on style and structure.
1. FACT -- Fact-checking 
1. SPELL -- Grammar and spell checking
1. GRAPH -- Graphics. Every piece needs a illustrated initial and at least one image.
1. FINAL -- Final look through before publication.

Notes for each pass are written (in Markdown) in STYLE.md, FACT.md, etc. Actual
corrections take place in the primary document. DO NOT put questions,
            annotations, etc, in the primary document -- we want this to be
            slowly transformed into something we can publish, without adding
            unpublishable bits. If you want to change the document profoundly,
            git add and commit before and after.