added set_border to novideo.py
fixed redrawing of screen when resuming from text interface to graphical
don't clear first char from screen buffer if pixel is put outside of screen
preserve border color on switch between width 40 and width 80 text mode
preserve border color on resume
don't preserve palette on mode switch - tis happened because palettes were referenced rather than copied
preserve LPT1 file connection on resume
reorganised state saving using copy_reg
implemented --state option to choose your own save-state file. Default now PCBASIC.SAV
implement --config option to choose config file