point9repeating

adds round_to_int boolean argument to FixedScaleOffset

1

Makes it possible to apply this filter without automatically converting to integers. #549

```python import numpy as np import numcodecs filter = numcodecs.fixedscaleoffset.FixedScaleOffset(273.15, 1.0, 'f4', astype='f4') # temp in K temperature = np.array([263.05, 273.05, 273.35, 283.25, 293.55, 304.05, 313.94998], dtype=np.float32) # scale temperature...