Bug 32672: Incorrect CSS path to jquery-ui

Bug 32672: Incorrect CSS path to jquery-ui

This patch removes links to jQueryUI assets which are not required in
the self-checkout and self-checkin pages.

The patch also adds missing JS to the self-checkin page related to
internationalization. This prevents a JS error related to an undefined
function, "__".

To test, apply the patch and view the main pages in self-checkout and
self-checkin, and the help page in self checkout. There should be no
errors in the browser console related to missing files.

Signed-off-by: David Nind <david@davidnind.com>
Signed-off-by: Martin Renvoize <martin.renvoize@ptfs-europe.com>
Signed-off-by: Tomas Cohen Arazi <tomascohen@theke.io>