Initial activation of indenting code (wikitext, ee665c4)

At the moment this breaks some of the specs but I wanted to get it in the repository in any case as it looks to be very nearly complete.

Will follow this up with edits to the specs to make them pass, as there are now many expected results that will need to be modified to include the indentation.

Signed-off-by: Greg Hurrell <greg@hurrell.net>