Fixing Curve2D/3D baked interpolated values

If bake interval is a multiple of the curve length, the curve would return NaN for some offset values (when `frac == 0.0`, it matches the start and end of the curve segment so `fmod == 0.0`, `frac` becomes NaN)

```
# Godot 3.1.1
var c = Curve3D.new()
c.add_point(Vector3())
c.add_point(Vector3(0.5,0,0))
c.add_point(Vector3(1,0,0))
c.bake_interval = 0.5
c.interpolate_baked(0.5) == Vector3(NAN, NAN, NAN)

```

0 files changed, 0 insertions, 0 deletions