docs: minor readme updates

[damorris25]

changes nanoTDF to NanoTDF, updates intro text to be cleaner 'read' as it's pulled into docusaurus site

Proposed Changes

Checklist

• A clear description of the change has been included in this PR.
• A clear description of whether this change is a Major, Minor, Patch or cosmetic change as per the Versioning Guidelines has been included in this PR.
• All schema validation tests have been updated appropriately and are passing.
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• DRAFT MERGE ONLY: Version numbers have been updated as per the Versioning Guidelines.
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