* Add support to allow the week day start in cal to be configurable
* Fix variable name
* Use a flag instead of a configuration setting for specifying the starting day of the week
* Don't include year and month by default, adds an option to display the quarters of the year
* Add a test for cal that checks that year requested is in the return
* rustfmt the cal tests
* Add cal command
* Fix docmentation to show commands on two lines
* Use bullet points on flag documentation for cal
* Dereference day before calling string method
* Silence Clippy warning regarding a function with too many arguments
* Update cal flag descriptions and documentation
* Add some tests for the cal command