Merge #175

175: Delete copy_memory function r=Dylan-DPC a=kinggoesgaming

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**I'm submitting a ...**
  - [ ] bug fix
  - [ ] feature enhancement
  - [x] deprecation or removal
  - [x] refactor

# Description
Replace `uuid::copy_memory` with `<[_]>::copy_from_slice`

# Motivation
`core` already provides a good optimized version of `slice` copying function, so we dont need to create our own duplicate code.

# Tests
Our tests and benchmarks are running good, other than one or two runs which suggest a 1-2 nanosecond slowdown.

# Related Issue(s)
#173

src/lib.rs

@@ -532,7 +532,7 @@ impl Uuid {
         hash.update(name.as_bytes());
         let buffer = hash.digest().bytes();
         let mut uuid = Uuid { bytes: [0; 16] };
-        copy_memory(&mut uuid.bytes, &buffer[..16]);
+        uuid.bytes.copy_from_slice(&buffer[..16]);
         uuid.set_variant(UuidVariant::RFC4122);
         uuid.set_version(UuidVersion::Sha1);
         uuid
@@ -647,7 +647,7 @@ impl Uuid {
         }
 
         let mut uuid = Uuid { bytes: [0; 16] };
-        copy_memory(&mut uuid.bytes, b);
+        uuid.bytes.copy_from_slice(b);
         Ok(uuid)
     }
 
@@ -992,12 +992,6 @@ impl Uuid {
     }
 }
 
-fn copy_memory(dst: &mut [u8], src: &[u8]) {
-    for (slot, val) in dst.iter_mut().zip(src.iter()) {
-        *slot = *val;
-    }
-}
-
 impl Default for Uuid {
     /// Returns the nil UUID, which is all zeroes
     fn default() -> Uuid {