Add version metadata to CytoTable Parquet output

[d33bs]

Description

This PR continues forward from work found within #132 . It adds version metadata to all Parquet output from CytoTable to address #19 . For review of this material I recommend focusing on changes under the /cytotable/ and /tests/ dirs (other changes are part of #132).

Closes #19

What is the nature of your change?

• Bug fix (fixes an issue).
• Enhancement (adds functionality).
• Breaking change (fix or feature that would cause existing functionality to not work as expected).
• This change requires a documentation update.

Checklist

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[d33bs]

Thank you @gwaybio ! I've addressed your comments and will merge this in now.