Vendor dependencies for 0.3.0 release

vendor/gilrs-core/examples/ev_core.rs

@@ -0,0 +1,12 @@
+use gilrs_core::Gilrs;
+
+fn main() {
+    env_logger::init();
+
+    let mut gilrs = Gilrs::new().unwrap();
+    loop {
+        while let Some(ev) = gilrs.next_event_blocking(None) {
+            println!("{:0x?}", ev);
+        }
+    }
+}