match-parameters: Formatting and re-ordering

Use floating images instead of tables.

Add headings ("False positives" and "The normed-absdiff confirm method")
to give some structure and break up the wall of text & images.

Don't introduce the "false source" image until the "False positives"
section. This allows us to show the "true source" image only once
instead of twice.
match-parameters: Edit wording.
match-parameters: layout/alignment change

This commit makes the figures align to the right hand side of the
containers, along with their labels. This means that the body text can
happily align left and wrap around the images which makes for easier
reading. The increase to .clear .figure margin makes the figures sit
slightly lower so that visually the text comes first.

The additional clear container was required in the article to prevent
the literal text block (the command) from overlaying on of the figures.