Show file paths (rebased onto develop)



This is the same as gh-2685 but rebased onto develop.

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Display the file path in a scrollpane and increase the border size to make it easier to resize.
see https://trac.openmicroscopy.org.uk/ome/ticket/12296
To test:
 * Select an image with more than one file associated to it e.g. dv or lei
 * Click on the show file paths.