Bugfix: OMEWikiComponents in metadata panel

This PR fixes http://trac.openmicroscopy.org.uk/ome/ticket/12684 and also makes the wiki syntax in the comments working properly (wiki syntax was interpreted before, too; but clicks on wiki objects weren't handled).

Test: Add some references to images by using the expression "image id: 123" in different ways (on it's own, in quotes, brackets, etc.) in the description and comments. Then double click on the links created, and make sure Insight does not crash and the correct image opens.