Add partial link filtering.

Doesn't quite work yet, but worth having this much.

Change-Id: I0f61761e121bb7d05c9b206b40316e6237a09496
Partial fix for the links not working.

Change-Id: I4db75f5ef67a3ebc01b62668e67753500a34c007
Make internal anchor links work

Change-Id: I3ef60f77635ac80433183bcc620844b7174f9a7b
Remove links within headers.

They're going to be links to themselves, which we don't
need (and which cause issues).

Change-Id: I210e47c6c190271a2460af22a148519ec43d9d32
Clarify print, also hide it.

Change-Id: Ia22d701711a5fd3ce66599fd8dc99427a58ee67a
Additional whitespace fixes to simplify pandoc.

Change-Id: Ib3f30bad4ec8bf4577eb94ab89a0de1ceb125a05