IR visitor API cleaning

All methods are now visitXYZ() instead of some methods being name
acceptXYZ().
Asciidoc callout fixes

Given a Golo-enabled Pygments, callouts need to be in comments to be
properly referenced.
json-simple integration
DynamicObject JSON helpers
JSON and structs
Improved stringify to support more and nested data
3rd-party mention of json-simple
Fix for missing recursive calls
Golodoc for gololang.JSON
Documentation for JSON
Merge pull request #142 from jponge/wip/json

json-simple integration
Asciidoc settings embedding
Fix: reset documentation when parsing augmentation
Fix: Test if section is empty
Merge pull request #147 from k33g/fix/function-doc-md

Fix: Test if section is empty
Change order of generated documentation
Merge branch 'improvement/sort-doc' into fix/function-doc
Merge pull request #145 from k33g/fix/function-doc

Fix: reset documentation when parsing augmentation
First sketch of DynamicVariable

This is directly modeled after scala.util.DynamicVariable.
Experimenting with observable composable refs

The current implementation has bugs. Fear!