Merge

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branch : feature/Pie_Chart
Merge

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branch : feature/Schema_Validation
Merged in charlie_x/openpyxl-ccr/feature/Schema_Validation (pull request #51)

Merged Schema Validation

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branch : 1.8
Update roadmap and make pytest test requirement.

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branch : 1.8
Updated coverage stats.

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branch : 1.8
Add additional requirements for test

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branch : 1.8
Updated install requirements.

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branch : 1.8
Fix indentation.

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branch : 1.8
Fix install commands

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branch : 1.8
Correct testrunner

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branch : 1.8
Python 3.2 seems to want an explciit string.

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branch : 1.8
Update docs

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branch : 1.8
lxml compatiblity

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lxml compatibility

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lxml compatibe

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branch : 1.8
More permissive checking whether lxml is there, easier to switch on and off.

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branch : 1.8
Use duck-typing instead of version.

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branch : 1.8
Prevent samples from being included in dist.

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branch : 1.8
Remove encoding declarations for compatbility with lxml

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branch : 1.8
Rationalise compatibility import

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branch : 1.8