Completely reformat markdown of API doc
Completely reformat markdown of API doc

This might or might not have solved the HTML-rendering problems we
were having in the json-block examples, but getting a true GitHub
preview is too hard, so I'm just going to keep committing on master
until the formatting problems are solved.  Hope this one's the one!

PCNI/OpenHMIS,PCNI/OpenHMIS,PCNI/OpenHMIS,PCNI/OpenHMIS