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ARROW-6669: [Rust] [DataFusion] Implement binary expression for physical plan

This PR adds the binary expression to the new physical execution plan, with support for comparison operators (`<`, `<=`, `>`, `>=`, `==`, `!=`) and boolean operators `AND` and `OR`.

Other binary expressions, such as math expressions will be added in a future PR.

Closes #5478 from andygrove/ARROW-6669 and squashes the following commits:

83bfa7705 <Andy Grove> formatting
af8d2982c <Andy Grove> address PR feedback
9ad3b7f6a <Andy Grove> formatting
bb82a24da <Andy Grove> use expect() instead of unwrap() when downcasting arrays
9b94cc8d9 <Andy Grove> Implement binary expression with support for comparison and boolean operators

Authored-by: Andy Grove <andygrove73@gmail.com>
Signed-off-by: Paddy Horan <paddyhoran@hotmail.com>