Bug 21335: Remove redundant includes of right-to-left.css

Bug 21335: Remove redundant includes of right-to-left.css

Fixes redundant includes of the right-to-left.css file.
There is no need to include it in the .tt files as it's part
of the doc-head-close.inc.

Note:
  Make sure your *BaseURL preferences are correctly set as
  this will make the switching between languages work
  correctly and throw you back to the start page otherwise
  every time you switch

Test:
- Install an RTL language like Arabic (ar-Arab)
- Test various pages with English and RTL language:
  - Authorities home page
  - Adding a new bibliographic record
  - Adding a new item or editing items
  - Advanced cataloguing (Rancor) editor
  - Labels start page
  - OPAC detail page
- Verify display is correct and right-to-left.css is available

Signed-off-by: Owen Leonard <oleonard@myacpl.org>
Signed-off-by: Charles Farmer <charles.farmer@inLibro.com>
Signed-off-by: Josef Moravec <josef.moravec@gmail.com>
Signed-off-by: Nick Clemens <nick@bywatersolutions.com>
(cherry picked from commit cdd14f05ae8672786e5306c41ff0f15ec9fed26f)
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>