Option to output 32-bit float samples

[Falcosoft]

'-af' option to output 32-bit float samples in order to preserve dynamic range and prevent clipping at the same time.
#59

Maybe also related to
#56

[Kappa971]

Impact on performance?

[pachuco]

neglijable

[Falcosoft]

I would say the performance is almost exactly the same (within 1%)