Resolve "Theme improvements"

Closes #4 (closed) #2 (closed)

This MR makes all the buttons I could find look "totemy". Buttons that had a blue border now have a #6c9 border. Buttons that had a blue background now function like Totem primary buttons (green background, yellow when hovered on).

Additionally, I removed the images on the bottom and replaced them with a small text saying we use open edx and tutor.

There was also 1 button that had the wrong size and had black text for some mysterious reason.

I adjusted its padding so it looks nice.

I also added a .editorconfig so you automatically use 2 spaces instead of tabs or a different multitude of spaces.