add a interface height and width to be used for the real interface resolution
make the SCREEN_HEIGHT, SCREEN_WIDTH a variable which can be set at start
parameters width and height
init screen size with INTERFACE size if not set from commandline
init some clipping rectgs and other static variables in init variables to get the correct screen size
do a default screen size init by the interface size, was removed by mistake
to much replaced, keep NORMAL_MAP_SCREEN_*
if the screen height is higher than 480 it seems we need some offset for the players drawing
or i missed a static variable
Revert as much as possible differences with the original Straccitella

preserving the new functionality at the same time.
Repositioning non-tactical UI to the center of the screen
Use command-like key '-res' to set video resolution

instead of two keys: '-width' and '-height'

Documentation updated.
Screenshots of the game with various resolutions
Add support of high video resolutions

Game can be started in 1024x768 mode like this: ja2.exe -res 1024x768
Any reasonable resolution should work.