Auto merge of #76 - mbrubeck:copy, r=jdm

Use copy_nonoverlapping in insert_from_slice

Since this method takes a unique reference to `self`, we know that it can't overlap with `slice`.

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Author: bors-servo

lib.rs

@@ -730,7 +730,7 @@ impl<A: Array> SmallVec<A> where A::Item: Copy {
             let slice_ptr = slice.as_ptr();
             let ptr = self.as_mut_ptr().offset(index as isize);
             ptr::copy(ptr, ptr.offset(slice.len() as isize), len - index);
-            ptr::copy(slice_ptr, ptr, slice.len());
+            ptr::copy_nonoverlapping(slice_ptr, ptr, slice.len());
             self.set_len(len + slice.len());
         }
     }