Fasttracker II clone v2.15

• BPM and voice/channel pitches are now tuned to better match original FT2.08/FT2.09 with an SB16 sound card at max audio output rate (44000Hz). If precise BPM is more important to you than FT2-accuracy, then check out the new "Precise BPM" option in Config -> Audio.
• Updated the help text to better reflect on the (default) FT2 BPM mode
• It's now possible to select a rate below 44100Hz when rendering song to WAV