Vendor dependencies

Let's see how I like this workflow.

vendor/iana-time-zone/examples/get_timezone.rs

@@ -0,0 +1,6 @@
+use iana_time_zone::{get_timezone, GetTimezoneError};
+
+fn main() -> Result<(), GetTimezoneError> {
+    println!("{}", get_timezone()?);
+    Ok(())
+}