[Feature request] Add a command to get download info given a game and an install path

[arielj]

It would be nice to have a command to get information about a potential download of a game in a specific installation directory, without actually installing the game in the process.

I imagine something like gogdl install-info game --install_dir="some path" (not sure if this follows the project's conventions, just an example)

The command would output at least this information:

• Total download size (the complete size of the game, without considering what was already downloaded)
• Total download size excluding re-usable files found in that installation dir (*)

(*) to add some clarification here, it's not the size of the uncompressed files in the disk, it's the size of the compressed files that would be downloaded, if the files on disk are uncompressed and the downloaded files are compressed we want the value of the compressed files which is the actual amount we are not re-downloading

We could include, as extra, some calculations with those numbers:

• remaining size: total - reusable to know how much is left in absolute units
• remaining %: (total - reusable) / total to know how much is left in %

These last extra numbers are not critical for this feature, we can calculate that with the other 2 values anyway