Replace images licensed with CC-BY-SA-2.x

Based on https://wiki.debian.org/DFSGLicenses#Creative_Commons_Attribution_License_.28CC-by.29.2C_v1.0 and https://wiki.debian.org/DFSGLicenses#Creative_Commons_Attribution_Share-Alike_.28CC-BY-SA.29_v3.0, both the CC-BY-SA-2.0 and CC-BY-SA-2.5 licenses are considered non-DFSG-compatible. So the package will be rejected by ftpmaster if it contains files under these licenses.

Here are the problematic files:

Files: static/themes/default/icons/deluge.svg
Copyright: Jakub Steiner, Tuomas Kuosmanen
Comment: https://git.deluge-torrent.org/deluge/tree/deluge/ui/data/icons/hicolor/scalable/apps/deluge.svg
License: CC-BY-SA-2.0

Files: doc/manual/en/images/icons/*
Copyright: 2003 Tango Desktop Project
Comment: https://github.com/moinwiki/moin-1.9/blob/master/docs/licenses/modernized.icons.txt
License: CC-BY-SA-2.5

Replace the files with DFSG-compatible licensed files.
If possible, ask upstream if the files can be replaced or re-licensed.