Macro routing::log_or_panic

macro_rules! log_or_panic {
    ($log_level:expr, $($arg:tt)*) => { ... };
}

This macro will panic with the given message if compiled with "use-mock-crust", otherwise it will simply log the message at the requested level.

Example usage: log_or_panic!(LogLevel::Warn, "{:?} Bad value: {}", self, value);