Testing:
- More tests for branching operations
- More tests for CMP/CPY/CPX operations
- Tests needed for JMP operations
- Tests needed for LD* and ST* operations
- Tests needed for IN* and DE* operations
- Tests needed for T** transfer operations
CPU:
- Stack operations and stack support in general
- Subroutines
- Decimal mode support
- Emulation mode support in general.
- Have each operation return the number of cycles used by the execute function.
- Implement the rest of the missing operations.
Memory:
- Banks
- ROM protection
- Memory mapped I/O
Display:
- Using the html page included provide a nice interface for using the cpu 
  emulator and provide many features helpful for debugging