Improve performance of index instruction by 1 cycle (fixed 1's complement

Improve speed of 1's complement calculation for add in instructions

Fix joystick.asm which broke because bzf got fixed.

Fix for bzf (it wasn't taking -0 into account) and Lunar Lander game works.

Moving the lunar lander with the joystick works.

Lunar lander falls properly now.

Make index instruction 1's complement.

Fixing some delay code in lunar lander game.

Adding more code to the lunar lander game.

Add function for drawing LEM.

Adding first part of a lunar lander program.

Fixes for some of the interrupt save registers and fixing joystick program.

Adding code to test joystick I/O.

LCD display can draw a box now.

Adding an SPI and inputs for a joystick.