Bug 36083: Fix HTML additional contents for the logged in branchcode

Bug 36083: Fix HTML additional contents for the logged in branchcode

This patch updates the calls to AdditionalContents.get() to use
Branches.GetLoggedInBranchcode instead of the logged in users
homebranch for the library parameter.

To test:
1. In Tools > HTML Customizations
2. Choose to create an entry in StaffAcquisitionsHome
3. Assign it to a specific library
   It's helpful to test with libraries other than Centerville
4. Add text and publication date (important or it will never display)
5. Save
6. Go to the Acquisitions Home page - logged into that library, no text displays.
7. Apply patch and refresh browser
8. Notice the library specifc content displays
9. Notice content created for all libraries still displays too
10. Test HTML content for specific libraries works on all 8 pages
    IntranetmainUserBlock
    Staff AcquisitionsHome
    StaffAuthoritiesHome
    StaffCataloguing Home
    StaffListsHome
    StaffPatronsHome
    StaffPOSHome
    StaffSerialsHome

Signed-off-by: Sam Lau <samalau@gmail.com>
Signed-off-by: Laura_Escamilla <laura.escamilla@bywatersolutions.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>