Release with the latest bitmap customizations

This custom version includes some changes to the memory mapped bitmap simulator to better aid students at University of Brasília by adapting RARS to the hardware limits of the FPGA used in the simulations:

• Custom 1 byte per pixel format (RRRGGGBB).
• Two different buffers for video frames.
• Swapping buffers in the bitmap simulator by changing a single byte in memory (0xFF20604).
• Further improvements to overall system stability and other minor adjustments have been made to enhance the user experience

The new features can be tested using the included blastoise.s file.
Updated with the fixes to the NOP instruction.