Use clap instead of getopts to parse cli args

`clap` allows using subcommands, which are helpfull for the input
methods. This also makes the main method a lot shorter, since there is
no need to add every single command line option per manually. This is
handled by the `derive` feature of `clap` and the new `Args` struct.

Author: wert007

Cargo.lock

@@ -7,5 +7,5 @@ edition = "2021"
 
 [dependencies]
 chrono = "*"
-getopts = "*"
+clap = { version = "*", features = ["derive"] }
 sysexits = "*"