Bug 5652: display subtitles on patron checkout and holds summary

Bug 5652: display subtitles on patron checkout and holds summary

This patch adds subtitles (from Keyword to MARC mapping) to the
following tables on the checkout page:

- Checkouts
- Previous checkouts
- Relative's checkouts
- Relative's previous checkouts
- Holds

Additionally it suppresses the appearence of the superfluous word "by"
in cases where the biblio has no author.

Test scenario:
--------------
1)
Make sure that you have one or more fields mapped to subtitle in:
Home . Administration . Keyword to MARC mapping
(e.g. 245 b)

2)
Test the checkout page with patrons having
- current checkouts (today)
- previous checkouts
- relatives (e.g. kids) with current /previous checkouts
- holds on items
- holds on biblios

...with items having:
- title, subtitle, author
- title,  no subtitle, author
- title,  subtitle, no author
- title, no subtitle, no author

3)
Do the same on patron's detail page

Signed-off-by: Nicole C. Engard <nengard@bywatersolutions.com>
All tests pass

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Chris Cormack <chrisc@catalyst.net.nz>
Signed-off-by: Galen Charlton <gmc@esilibrary.com>