New improved VGA/MCGA capture and test

Test program TEST-FW/VIDEO/PC/TEST and HW/VGA/TMODESET now captures INT 1Dh CGA/MDA compatible video parameter block, and EGA/VGA/MCGA video parameter block via BIOS 40:A8

VGA2 library, minimal detection routines and minimal alphanumeric memory layout code.

VGA2 test program to set up stride or display width on MDA/CGA/PCjr/Tandy/MCGA/EGA/VGA, experimental