Additional Documentation

[Pickysaurus]

Created a new "Adding Games" page to user docs.
Improved the "Getting Started" page by adding buttons to the Windows/Linux download options and mentioning the Linux packages.
Corrects several small mistakes in existing docs.

[erri120]

Images should also be WebP, binary blobs can make git checkout very slow over time. Make sure to use a rebase for this, so that the original PNGs aren't in the history. We'll squash merge.

[Pickysaurus]

Images should also be WebP, binary blobs can make git checkout very slow over time. Make sure to use a rebase for this, so that the original PNGs aren't in the history.

There is not a good way to create WebPs on Windows. I can compress them as JPGs or we can split the docs off into a submodule?

[erri120]

Images should also be WebP, binary blobs can make git checkout very slow over time. Make sure to use a rebase for this, so that the original PNGs aren't in the history.

There is not a good way to create WebPs on Windows. I can compress them as JPGs or we can split the docs off into a submodule?

I'll turn them into WebPs. Most editing software should be able to do this tho (Paint.NET, GIMP, Photoshop).

Requested changes were handled