added missing documenatation for option data_only
Merge

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Added tag 1.8.2 for changeset 2c67790bd792
Merge

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Prevented raising of NotImplementedError when loading a worksheet with
comments with use_iterators=True

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branch : 1.8
Update docs.

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branch : 1.8
No longer need to pass in the name of the workbook file.

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Update docs

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branch : 1.8
Merge in pull request #75
Added tag 1.8.2 for changeset 581cf3b4ccb5
Merge in pull request #75

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branch : 1.9