Fixing broken links in BF doc build (rebased onto develop)


This is the same as gh-725 but rebased onto develop.

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Molecular Imaging Corp appears to have closed, explaining why their website doesn't exist anymore (delisted on stock exchange sites and reported closed on local business finder website, also investors forum posts saying it has gone bust).

Imaris link is the closest I can find to a current features page - you have to click on a 'Features' tab.

This PR should make the BF docs-merge-develop build green again.