Merge #268

268: impl Hash for CharRange r=CAD97 a=CAD97

I don't know why we didn't have this already /shrug

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Co-authored-by: Christopher Durham <[email protected]>

unic/char/range/src/range.rs

@@ -34,7 +34,7 @@ use crate::CharIter;
 /// If constructed in reverse order, such that `self.high` is ordered before `self.low`,
 /// the range is empty. If you want to iterate in decreasing order, use `.iter().rev()`.
 /// All empty ranges are considered equal no matter the internal state.
-#[derive(Copy, Clone, Debug, Eq)]
+#[derive(Copy, Clone, Debug, Eq, Hash)]
 pub struct CharRange {
     /// The lowest character in this range (inclusive).
     pub low: char,