Update to 1.3.0

Changelog from https://pydicom.github.io/pydicom/stable/release-notes.html

Documentation

• New User Guide page for Python 2 support timeline
• New User Guide page for working with private data elements
• example loading set of CT slices and plotting axial, sagittal and coronal (#789)

Changes

• Removed deprecated uid variables, config.image_handlers and DeferredDataElement (#760)
• dataelem.isMultiValue is deprecated and will be removed in v1.4. Use dataelem.DataElement.VM instead.
• dataelem.isStringOrStringList and dataelem.isString functions are removed
• datadict.add_dict_entry and datadict.add_dict_entries now raise if trying to add a private tag
• dataset.Dataset.maxBytesToDisplay also limits display length for non-binary VRs (by number of items) (#666)

Enhancements

• Added datadict.add_private_dict_entry and datadict.add_private_dict_entries to add custom private tags (#799)
• Added possibility to write into zip file using gzip, by avoiding seek (#753)
• Added RLE encoding (#730)
• Added handling of incorrect transfer syntax (explicit vs implicit) (#820)
• Added creation of Tag instances by DICOM keyword, e.g Tag(“PatientName”)
• Added possibility to get and add private tags without adding them to the private dictionary
• Added possibility to use a Dataset in a NumPy array
• Allow missing padding byte in Pixel Data, issue a warning in this case (#864)
• Add in-memory image decoding with GDCM
• Check really used implicit/explicit VR before reading a data set (#819, #820)
• Added alpha conversion of Datasets to/from JSON format (Python 3 only)

Fixes

• Correctly handle Dataset.pop and Dataset.setdefault for tuple and keyword arguments (#852)
• Correctly handle encoding errors when any of the encodings are invalid (not just the first) (#850)
• Do not raise while resolving an ambiguous VR dependent on PixelRepresentation if both PixelRepresentation and PixelData are not present (#838)
• Raise exception with specific message if value is too large to be written in explicit transfer syntax (#757)
• Make hash for PersonName3 behave as expected, make PersonName objects immutable (#785)
• Fixed generate_uid() returning non-conformant UIDs when prefix=None (#788)
• Avoid exception if reading from empty file (#810)
• An invalid encoding is now replaced by the default encoding, if config.enforce_valid_values is not set (#815)
• Correctly handle elements with ambiguous VR in sequence items (#804)
• Fix bug where new DicomDir objects always have is_implicit_VR
• Fix dataset equality for mixed raw vs converted data elements (#835)
• Remove excess padding in Pixel Data
• Fix wrong date format in anonymize example
• Fix unknown VR exception message when VR isn’t ASCII (#791)
• Fix jis-x-0201 characters encoding (#856)