Marking up example links (rebased onto dev_4_4)



This is the same as gh-527 but rebased onto dev_4_4.

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The link checker in the build is trying to check these links even though they are not marked up as hyperlinks for some reason. This is to make it clear they are examples not actual links. To test, check that omero-docs-merge-develop is not showing these as broken links ('Name or service not known) anymore (it will still be yellow due to 'Anchors not found').