Add support for uploading tag images through Taxonomy Editor

[teolemon]

Problem

• Tag images is a complicated process
• It's also a very time consuming one, when you consider the long tail of Brand logos and Non food products quality sign (and the international long tail)
• Add support for uploading tag images through Taxonomy Editor
• The system would have a check on dimensions
• It would have support for PNG and SVG versions, nudging people to find a proper SVG file
• It would have support for monochrome versions
• It would even have a built-in cropper to help people transform existing logos into a better logo (square, white or transparent background, etc…)
• We could make this a system independant from taxonomy editor
• We should research if anyone has created a similar system on GitHub.