License review / Replace images with unclear license provenance (`editor/images`)

I have been reviewing the license content of svgedit, and added a couple badges to indicate the licenses of the repo and its bundled dependencies (and one for devDependencies). Any feedback would be welcome.

~Anyways, when searching for license info within svgedit, I discovered that there is at least one SVG file with the viral license “CC-BY-SA-2.0”. See https://creativecommons.org/licenses/by-sa/2.0/ . My review has found that no other licenses in our package, including bundled dependencies (and we have no dependencies) are explicitly virally restrictive besides this one.~

~Since we don’t want to be required to make the library require compliance with this license type (assuming it is even compatible with the rest of the licenses), we really need to substitute this image.~

~The image that was labeled with this license was editor/images/polygon.svg (and presumably a file generated from it, editor/images/polygon.png)–a small polygon (http://creativecommons.org/licenses/by-sa/2.0/ is referenced in source).~ The other files in that directory do not have clear license information, merely stating a source for some files.

~While~ I think we should replace all of these icons ~, for starters, I think we really need to avoid this dependency.~

Update: we have replaced the explicitly protective (CC-BY-SA-2.0) license file, but still are unclear on the license status of the other image files.

[jfhenon]

We recreated icons as SVG in V7 under the MIT licence

[brettz9]

Did you wish to change the license terms?