update icons to recent Tango versions with more permissive license

Submitted by Yves-Alexis Perez

Assigned to Xfburn Bug Triage

Hi,

it seems that some icons shipped in xfburn are derived from Tango icons at a time they were license under CC-BY-SA 2.0, which is not DFSG free (http://evan.prodromou.name/ccsummary/ccsummary.html).

Would it be possible to update them using latest Tango icons, which are released under public domain?

Version: SVN trunk