including org files is more complex - e.g. footnotes need to be namespaced to
their source file. org does this by prefixing each included files footnotes
with a number - but even that is not enough as it doesn't guarantee
uniqueness.
As I don't have a usecase for it, I'll avoid the additional complexity for
now.
- was missing spaces between attributes when rendering to org
- was duplicating attributes when rendering to html - now we join / replace
attributes depending on the name - for now only class & style are appended
... hopefully correctly
This will hopefully improve ease of developing (more granular test results) and
prepares us for adding example org->html renders for gh-pages
