[FEAT REQ] Cross-compatible way to install older versions of MangDL

[whinee]

Is your feature request related to a problem? Please describe.

Yes, as the sole maintainer of this shitty project, I find it very frustrating to pin down at what version did a certain bug appeared and such. Even though the changelog is written as clearly as possible, some undocumented refactoring of code might cause breakages to the project.

Describe the solution you'd like

I want to be able to install specific versions of MangDL.

Describe alternatives you've considered

For linux distros, downloading the AppImages from the github releases and installing them manually to my machine. As for windows, downloading the zip for windows and unpacking it manually to the correct directory.