Complex numbers support

[pierreguilmin]

Thanks a lot for your excellent library! 👏

When integrating a complex-valued function, for example just just changing the README example to fun = lambda t: t * jnp.log(1 + t) * 1j, I get a TypeError:

TypeError: true_fun and false_fun output must have identical types, got
('ShapedArray(complex64[])', 'ShapedArray(float32[], weak_type=True)', 'DIFFERENT ShapedArray(complex64[]) vs. ShapedArray(float32[])', 'DIFFERENT ShapedArray(complex64[]) vs. ShapedArray(float32[])').

This happens even when the norm is real-valued (which is the default anyway I think).

[f0uriest]

Thanks, this was due to some type mismatches when shortcutting a zero length interval. Should be fixed by #20