* images/spinner.png, images/background-li.png: New images converted
from gif.
* *.php: Changed several files from spinner.gif to spinner.png.
* extensions/update_manager/settings.php: Changed header.
git-svn-id: https://svn.code.sf.net/p/pandora/code/trunk@2124 c3f86ba8-e40f-0410-aaad-9ba5e7f4b01f
raulmateos