Rollup merge of rust-lang#21846 - tbu-:pr_revert_uncopyable_range, r=

 This reverts commit c3841b9.

The commit made it impossible to copy the pretty fundamental data type `Range` and `RangeFrom`, which e.g. means that they can't be used in otherwise copyable structures anymore (or `Cell`s for that matter), where the reason for removal was that it can *also be used as an iterator*.

CC @japaric
rust-lang#21809

src/libcore/ops.rs

@@ -974,7 +974,7 @@ impl fmt::Debug for RangeFull {
 }
 
 /// A (half-open) range which is bounded at both ends.
-#[derive(Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, PartialEq, Eq)]
 #[lang="range"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct Range<Idx> {
@@ -994,7 +994,7 @@ impl<Idx: fmt::Debug> fmt::Debug for Range<Idx> {
 }
 
 /// A range which is only bounded below.
-#[derive(Clone, PartialEq, Eq)]
+#[derive(Copy, Clone, PartialEq, Eq)]
 #[lang="range_from"]
 #[stable(feature = "rust1", since = "1.0.0")]
 pub struct RangeFrom<Idx> {