Almost alpha

• Clean error handling that doesn't hose the program on a hiccup.
  • Errors are now displayed on the screen.
  • You can simply refresh the page if an error occurs. (Errors will occur due to race conditions in GUI.)
• Link formatting implemented, but no clickback yet. So, it's practically useless.
• Colours adjustable in config.rkt
• Downloading works.
• Stop feature removed until seamless threading (heh heh)