* the price-guide uses the revamped AffilateV1 API, if an API key is
available at compile time. Otherwise the old method is used.
* price-guides can have VAT included or not (to varying degrees,
based on the backend)
* all pictures are now converted to WEBP lossy at 90% after
downloading, which compresses to around 10-20% of the
original PNG size without obvious visual artifacts.
* both the price-guide data and pictures are not written to
individual files in the cache folder anymore. Instead 2 sqlite
databases will be used (faster lookups, easier cache upgrades in
the future, less space wasted in the file-system)
Closes: #80
Some of the SVG flags were not SVG 1.2 tiny compatible, resulting in
rendering artifacts. Also, the size of the 100px flags is sufficient
and they are just 900K in total (vs. 4.2M for the SVGs)
Robert Griebl