Update jquery.uls from upstream.

Upstream: https://github.com/wikimedia/jquery.uls
Changes:
1. Optimize png images with optipng -o7
2. Optimize language icon SVG
3. Optimize the search and worldmap svgs
4. Localization updates.

Change-Id: Ic921b31830b0d7a1424d9d663924e92b9c5268f1