Bug 8644 [staff client] jQueryUI CSS file should not contain customizations

Bug 8644 [staff client] jQueryUI CSS file should not contain customizations

This patch moves jQueryUI customizations into the main CSS
file for the staff client. In order to get the corrected
default version of jquery-ui.css I have upgraded all core
jQueryUI files.

Testers should look at examples of each of the various jQueryUI
widgets we use in Koha to confirm continued functinality: tabs,
autocomplete, datepickers, and slider (in specify due date popup).

Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>