Clarify and fix Bio-Formats Fiji documentation

Explain that Fiji ships with the latest Bio-Formats stable release,
that you can enable daily builds, and link to the Fiji wiki page for
further details.
Remove link to ImgLib2 Fiji wiki page

The site imglib2.net redirects to that same page anyway.
And imglib2.net is a more future-proof URL in any case.
Use "See also" boxes where relevant
Rework out-of-date FARSIGHT documentation

The code formerly known as BF-ITK is now integrated directly into ITK,
and as such much of this information has been simplified. The
Bio-Formats ITK page has most of the informational meat; the FARSIGHT
page merely needs to mention that it uses ITK to harness Bio-Formats.
Use better and shorter Fiji wiki URLs

The "/wiki/index.php" is not needed.
Update Image5D link
Use U.S. English spelling of "focuses"
Split out main doc sections with bullets

We were already listing them as bullets, but then we also redundantly
linked to them in the introductory paragraph above as well.

Bulleted lists are often much easier to read and digest
(http://www.contentious.com/2004/09/17/bulleted-lists/), so let's just
stick to a single list with the description inline per bullet point.
Update ImgOpener link to current implementation