This LFO uses an unsigned 32-bit phase and increment whose 8 Most Significant Bits adress
a Look-up table while the 24 Least Significant Bits are used as the fractionnal part.
Note: As the phase overflow automatically, the index is always in the range 0-255.
It performs linear interpolation, but it is easy to add other types of interpolation.
Don't know how good it could be as an oscillator, but I found it good enough for a LFO.
BTW there is also different kind of waveforms.
We could use phase on 64-bit or change the proportion of bits used by the index and the