* add variance (population)
subcommand to math
* impl variance subcommand with spanning errors for invalid types
* add stddev subcommand to math
* rename bytes to filesize
* clippy fix -- use expect instead of unwrap in variance tests
* Update calculate to return a table when Value is a table
* impl mode subcommand for math
* add tests for math mode subcommand
* add table/row tests for math mode subcommand
* fix formatting
* Converting average.rs to math.rs
* Making some progress towards math
Examples and unit tests failing, also think I found a bug with passing in strings
* Fix typos
* Found issue with negative numbers
* Add some comments
* Split commands like in split and str_ but do not register?
* register commands in cli
* Address clippy warnings
* Fix bad examples
* Make the example failure message more helpful
* Replace unwraps
* Use compare_values to avoid coercion issues
* Remove unneeded code
