Checks for updates to the crate, and prints a message if an update is available
Given a possibly undefined version number, check if it’s present and supported
Given a key, get the value from the environmental variables, and print it to the console
Gets the latest version of the crate from crates.io
Prints the AdGuardian ASCII art to console
Print error message, along with (optional) stack trace, then exit
Reusable function that just prints success messages to the console
With the users specified AdGuard details, verify the connection (exit on fail)
Initiate the welcome script
This function will: