Linux: Embed AppImage update information

[shuvashish76]

Describe feature

AppImage delta updates which will take less amount of data and time due to downloading only diff.

Additional Information

When trying to update via AppImageUpdate

AppImage having update information would also recognized by other software e.g. AppImageLauncher , AppImageUpdate, AppManager, AM etc...

info:

• https://github.com/AppImageCommunity/AppImageUpdate#update-information-overview
• https://github.com/AppImage/AppImageSpec/blob/master/draft.md#update-information
• https://github.com/ivan-hc/AppImage-tips#how-to-add-delta-updates

Lots of projects already support updating AppImage e.g: LibreWolf, KeePassXC, Sigil etc.