LP#1681009 Merge the RTL style with the LTR style

LP#1681009 Merge the RTL style with the LTR style

Rather than adding the right-to-left stylesheet
Open-ILS/src/templates/opac/css/style-rtl.css.tt2 as something that
gets included in addition to the LTR style.css.tt2 when a RTL language is in
play, merge the logic directly into the stylesheet so that we save bytes over
the network, browser rendering time, and reduce the possibility that RTL will
be forgotten about when new features are added or styles are optimized.

Signed-off-by: Dan Scott <dan@coffeecode.net>
Signed-off-by: Ben Shum <ben@evergreener.net>
Signed-off-by: Kathy Lussier <klussier@masslnc.org>