Vendor dependencies

Let's see how I like this workflow.

vendor/rdrand/benches/rdrand.rs

@@ -0,0 +1,49 @@
+#![feature(test)]
+extern crate rand_core;
+extern crate rdrand;
+extern crate test;
+
+use rand_core::RngCore;
+use test::Bencher;
+
+#[bench]
+fn bench_u16(b : &mut Bencher) {
+    if let Ok(gen) = rdrand::RdRand::new() {
+        b.bytes = 2;
+        b.iter(|| {
+            gen.try_next_u16().unwrap()
+        });
+    }
+}
+
+#[bench]
+fn bench_u32(b : &mut Bencher) {
+    if let Ok(mut gen) = rdrand::RdRand::new() {
+        b.bytes = 4;
+        b.iter(|| {
+            gen.next_u32()
+        });
+    }
+}
+
+#[bench]
+fn bench_u64(b : &mut Bencher) {
+    if let Ok(mut gen) = rdrand::RdRand::new() {
+        b.bytes = 8;
+        b.iter(|| {
+            gen.next_u64()
+        });
+    }
+}
+
+#[bench]
+fn bench_fill(b : &mut Bencher) {
+    if let Ok(mut gen) = rdrand::RdRand::new() {
+        let mut buffer = [0; 128];
+        b.bytes = 128;
+        b.iter(|| {
+            gen.fill_bytes(&mut buffer);
+            buffer
+        });
+    }
+}