Vendor dependencies

Let's see how I like this workflow.

vendor/rand/benches/distributions/gamma.rs

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+use std::mem::size_of;
+use test::Bencher;
+use rand;
+use rand::distributions::IndependentSample;
+use rand::distributions::gamma::Gamma;
+
+#[bench]
+fn bench_gamma_large_shape(b: &mut Bencher) {
+    let gamma = Gamma::new(10., 1.0);
+    let mut rng = rand::weak_rng();
+
+    b.iter(|| {
+        for _ in 0..::RAND_BENCH_N {
+            gamma.ind_sample(&mut rng);
+        }
+    });
+    b.bytes = size_of::<f64>() as u64 * ::RAND_BENCH_N;
+}
+
+#[bench]
+fn bench_gamma_small_shape(b: &mut Bencher) {
+    let gamma = Gamma::new(0.1, 1.0);
+    let mut rng = rand::weak_rng();
+
+    b.iter(|| {
+        for _ in 0..::RAND_BENCH_N {
+            gamma.ind_sample(&mut rng);
+        }
+    });
+    b.bytes = size_of::<f64>() as u64 * ::RAND_BENCH_N;
+}