Refactor to allow testing of unique names.

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branch : 1.8
Initial fix based on pull request 72

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Merge
Removed tag 1.8.2
Added tag 1.8.2 for changeset 8cc75d2525eb
Update docs resolves #253

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Merge
Update docs
Removed tag 1.8.2
Added tag 1.8.2 for changeset 4d17509417df
Merge

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Replace module with package.

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rename : openpyxl/cells/__init__.py => openpyxl/cell/__init__.py
rename : openpyxl/cells/cell.py => openpyxl/cell/cell.py
Replace module with package

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Replace module with package

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rename : openpyxl/workbook.py => openpyxl/workbook/workbook.py
Replace module with package

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rename : openpyxl/worksheet.py => openpyxl/worksheet/worksheet.py
Replace module with package

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rename : openpyxl/drawing.py => openpyxl/drawing/drawing.py
Replace module with package

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rename : openpyxl/comments.py => openpyxl/comments/comments.py
Module has been replaced by a package

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Moved to cell package.

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rename : openpyxl/formula.py => openpyxl/cell/formula.py
Break out „shared“ folder. Additional namespace is not really required. compat, xml, exceptions, units and date_time can all be library modules or packages.

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branch : 1.9
rename : openpyxl/shared/compat/__init__.py => openpyxl/compat/__init__.py
rename : openpyxl/shared/compat/itertools.py => openpyxl/compat/itertools.py
rename : openpyxl/shared/compat/numbers.py => openpyxl/compat/numbers.py
rename : openpyxl/shared/compat/odict.py => openpyxl/compat/odict.py
rename : openpyxl/shared/compat/strings.py => openpyxl/compat/strings.py
rename : openpyxl/shared/date_time.py => openpyxl/date_time.py
rename : openpyxl/shared/exc.py => openpyxl/exceptions.py
rename : openpyxl/shared/units.py => openpyxl/units.py
rename : openpyxl/shared/password_hasher.py => openpyxl/worksheet/password_hasher.py
rename : openpyxl/shared/namespace.py => openpyxl/xml/namespace.py
rename : openpyxl/shared/ooxml.py => openpyxl/xml/ooxml.py
rename : openpyxl/shared/xmltools.py => openpyxl/xml/xmltools.py