v1.0

• Support colours in text mode (GOSUB 110).
• Add a splash screen (playable with the -intro command line parameter).
• Adopt MIDI for better sound.
• Default prompt for INPUT.
• Support for slowing down execution.
• Show a cursor on INPUT.
• Show more detailed stack traces and variable/array values when errors occur.
• Display error information in a window instead of on the console only.
• Open a file picker if a directory is given on the command line.
• Support running subroutines with GOTO (implicit RETURN).
• Bug fixes:
  • GOSUB 450 should modify interpreter state (SD, IN, IN$).
  • Support special characters (STX, ETX, FS) in 8-bit era files.
  • Avoid deleting the entire line with backspace on INPUT.
  • Treat variable names always as upper case internally.
  • Address graphics quantisation gap.