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ARROW-4337: [C#] Implemented Fluent API for building arrays and record batches

Implemented Fluent API for building arrays and record batches. Includes some unit tests for builders but more work is needed to improve coverage.

Replaces #3574 by rebasing on latest master and addressing PR feedback. I couldn't push to that branch, so I needed to create a new PR.

/cc @chutchinson @pgovind @wesm

Author: Eric Erhardt <eric.erhardt@microsoft.com>
Author: Christopher Hutchinson <cshutchinson@fzcorp.com>

Closes #4640 from eerhardt/4337-array-builder-api and squashes the following commits:

51499da8a <Eric Erhardt> Fix unit tests and rat exclude files.
235ba4909 <Eric Erhardt> Respond to PR feedback
5d97cbfaa <Christopher Hutchinson> Implemented Fluent API for building arrays and record batches