- add TextQuoteSelector.from_text shortcut - add ability to subtract an integer from all values in a TextPositionSet - include [marshmallow](https://github.com/marshmallow-code/marshmallow) schema for serializing
0.2.1
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- add init file to utils directory
0.2.0
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- Make TextPositionSelector subclass `Range` from [python-ranges](https://github.com/Superbird11/ranges).
0.1.1
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- add init file to tests directory
0.1.0
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- Create TextPositionSelector and TextQuoteSelector classes