Drop PartialEq impl for Regex (fixes rust-lang#178)

src/re_unicode.rs

@@ -133,18 +133,6 @@ impl From<Exec> for Regex {
     }
 }
 
-/// Equality comparison is based on the original string. It is possible that
-/// different regular expressions have the same matching behavior, but are
-/// still compared unequal. For example, `\d+` and `\d\d*` match the same set
-/// of strings, but are not considered equal.
-impl PartialEq for Regex {
-    fn eq(&self, other: &Regex) -> bool {
-        self.as_str() == other.as_str()
-    }
-}
-
-impl Eq for Regex {}
-
 impl FromStr for Regex {
     type Err = Error;