TODO

 - Emulate basic kernal routines (see: https://sta.c64.org/cbm64krnfunc.html)
   * No need for serial stuff, etc. - just the basics
   * Basic file handling (SETLFS, SETNAM, LOAD, SAVE)
   * File handling (OPEN, CLOSE, SETLFS, SETNAM, CHKIN, CHKOUT)
    - see https://www.lemon64.com/forum/viewtopic.php?t=64677&highlight=scratch
    - to scratch you can just call SETLFS then SETNAM with name of "S0:FILE_TO_DELETE"
      ...after calling OPEN this will delete the file (CLOSE after)
    - can do similar for rename (e.g. "R:newname=oldname")?
   * Character ouput (CHROUT, PLOT maybe) - necessary for writing files
   * LOAD / SAVE routines? Helpful for verifying
   * Input? (GETIN, CHRIN)
 - VIC chip
   * Sprites
   * Changing screen RAM location, etc.
   * Color RAM
 - Emulate CIA (see: https://www.c64-wiki.com/wiki/CIA)
   * Also see: https://retrocomputing.stackexchange.com/questions/6421/reading-both-keyboard-and-joystick-with-non-kernal-code-on-c64
 - Perhaps we can bundle basic? (See: cbmbasic in IDEAS)