Onscreen IDE & dynamic instant update [_v0.5.4_]

Done.
Found a bug already. I missed the rstrip(’\n’) in delLine, caused a havoc to the indentation.

QUICK UPDATE :

  1. able to load files, press Ctrl-O
  2. I don’t like filling my screen with files’ tabs, so I make the tabs draggable sideways. Use MMB to slide it, and Ctrl-MMB to close a file.