Dolby Prologic surround (or something similar) DSP plugin v1.54.2 for Mpxplay

Put this DLL in the directory of Mpxplay and the program will use it 
automatically instead of the built-in surround (wide-stereo) effect.

Use -sr option or ; and ' keys to configure it.
Good value is somewhere between 110 and 300.

note1: it has a nice, but very small effect only
note2: it works only in HQ mode (the LQ part uses the old effect)
note3: It's not finalized, not tuned properly yet (usually it's good for 
       instrumental/classical music only)...
