Add fields for donations, bug tracker and translations

[Jacalz]

The field for homepage is there, but it would be great if we could input links for donations and bug tracker.

Example:

  <url type="bugtracker">https://github.com/Jacalz/rymdport/issues</url>
  <url type="donation">https://github.com/sponsors/Jacalz</url>

Also translations:

https://github.com/Beep6581/RawTherapee/blob/59a36d8f8a79918749a9da298bf559a0cedc4cf8/com.rawtherapee.RawTherapee.appdata.xml#L22