Vendor dependencies for 0.3.0 release

vendor/tracing-log/tests/reexport_log_crate.rs

@@ -0,0 +1,10 @@
+use tracing_log::{log::LevelFilter, LogTracer};
+
+/// This test makes sure we can access `log::LevelFilter` through the `tracing_log` crate and don't
+/// have to depend on `log` separately.
+///
+/// See https://github.com/tokio-rs/tracing/issues/552.
+#[test]
+fn can_initialize_log_tracer_with_level() {
+    LogTracer::init_with_filter(LevelFilter::Error).unwrap();
+}