Imagedata

Fixed
* Header: When using a template to create DicomHeaderDict, use deepcopy to get a unique
DicomHeaderDict for the new instance.
Added
* Viewer: Save window center/width to Series object when returning.
* Series.fuse_mask(): New parameter `blend` which determines whether
the self image is blended. Default is False, such that the self image is
not blended, only the mask is blended.

Fixed
* Series: Handle the special case when an ufunc is called with a where= Series object used
by NumPy >= 1.25.
* Series.write(): Updated documentation on 'window' option.

Added
* Series.write(..., opts={'window': 'original'}): Use original
window center/level from data object, do not calculate window
from present data.
* Viewer: Accept MONOCHROME1 photometric interpretation, using the Greys colormap.
Fixed
* Viewer: Re-enabled linked scrolling of several image series.

Fixed
* Error in documentation example on drawing a time curve when mask is moved. Fixed.
* Viewer: Updated MyPolygonSelector to match Matplotlib 3.8.
* Require numpy < 1.25 as temporary fix, due to a mismatch where array_likes can override
ufuncs if used as `where=`.

Fixed
* Series: Protect for NaN values.
* Viewer: Protect for NaN values.
* Viewer: Display real part only of complex values.

Fixed
* Added sphinx_rtd_theme as requirement.