item page: enlarge image, reduce white space
Merge branch 'dev/itempageformat' into develop
Add link to exhibit/exhibit page in item page

Added initial code that will add a link back to the exhibit
and the exhibit page, as well as all related exhibit pages.
The code is not finalized, need to commit to be able to merge.
Merge branch 'dev/itemlinkback' into develop
Add link to exhibit and exhibit page(s) in item page

Note that some of this functionality is in the plugin/CulCustomize,
which is in its own repo. The code we added here in this commit
makes use the following helper function from CulCustomize:
cul_display_links_to_exhibit_pages_containing_item()