implement a draw_rect function

[tsatke]

Implements a probably efficient draw_rect function, as well as some refactoring to make space for more implementations such as draw_triangle or draw_sphere.

[RKennedy9064]

@tsatke Would you mind fixing the merge conflicts for this branch so I can merge it in. Once this is merged I'll make a new release containing this and the new graphics mode you implemented.

[tsatke]

@RKennedy9064 done 🙂

[tsatke]

ping @RKennedy9064

[RKennedy9064]

@tsatke Thanks for the contribution. I'll try to get a new version published sometime tomorrow!