Bump Version Number and RevisionNumber time baseline

[QilongTang]

Please Note:

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Purpose

Bump up version number and Revision Number time baseline in master branch per creation of RC branche https://github.com/DynamoDS/Dynamo/tree/RC2.1.0_master

Declarations

Check these if you believe they are true

• The code base is in a better state after this PR
• Is documented according to the standards
• The level of testing this PR includes is appropriate
• User facing strings, if any, are extracted into *.resx files
• All tests pass using the self-service CI.
• Snapshot of UI changes, if any.
• Changes to the API follow Semantic Versioning, and are documented in the API Changes document.

Reviewers

FYIs

@mjkkirschner @ColinDayOrg @alfarok @reddyashish @scottmitchell @aparajit-pratap