Bug 18743: Fix suggestion listing when organized by library

Bug 18743: Fix suggestion listing when organized by library

There are some weird behaviors happening when using the "Organize by:
library" dropdown along with the library filter (in the "Acquisition
information" box).

I am suggesting the following test plan:
0. Create several suggestion from different libraries

A. You are superlibrarian and IndependentBranches is not set (=No)
1. Hit /suggestion/suggestion.pl
=> Default view shows the suggestions from your library
2. Filter by another library
=> You see the suggestions from this library
3. Filter by "Any" libraries
=> You see all the suggestions
4. "Organize by library"
=> You see all the suggestions, organized by library
5. Filter by a specific library
=> You see the suggestion from your library, all in one tab

B. You are not superlibrarian and IndependentBranches is not set (=No)
Same as A.

C. You are superlibrarian and IndependentBranches is set
Same as A.

D. You are not superlibrarian and IndependentBranches is set
You will never see suggestions coming from outside your library

QA: To be clear: the whole script needs a rewrite, but here we are just
trying to fix weird behaviors.

Sponsored-by: BULAC - http://www.bulac.fr/
Signed-off-by: Séverine QUEUNE <severine.queune@bulac.fr>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
(cherry picked from commit 9f16ab9e758aeb1a9e64bde03c6c8dcfb7f6e094)
Signed-off-by: Fridolin Somers <fridolin.somers@biblibre.com>