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