config.c
- added functions cfgSetVerticalScaleStrategy, cfgGetVerticalScaleStrategy, cfgGetVerticalScaleStrategyFromString, cfgGetLinemodeStrategyToString
- added code to service the scaling strategy configuration items
draw.c
- added variable draw_vscale_strategy
- added functions drawSetVerticalScaleStrategy and drawGetVerticalScaleStrategy
- several changes to different function to facilitate 2x exact scaling
- for every color depth added functions to get 1x1, 1x2, 2x1 and 2x2 pixel scaling
gfxdrv.c
- several changes to different function to facilitate 2x exact scaling (blitting to DirectX surface)
wgui.c
- added code to select different strategies for vertical pixel scaling