Demos: Merge HelloWorld into CoolWorld

[AnErrupTion]

Hello there! This PR merges the Mosa.BareMetal.HelloWorld demo into the Mosa.BareMetal.CoolWorld demo, with the goal of having only 1 flagship demo. No code was actually changed, though the following changes were done:

• The documentation was updated to reflect the changes
• The demo scripts were renamed accordingly (HelloWorld -> Console.CoolWorld, CoolWorld -> Graphical.CoolWorld)
• Demo images in the documentation were fixed