gnu: Add rust-num-rational-0.3.

* gnu/packages/crates-io.scm (rust-num-rational-0.3): New variable.
(rust-num-rational-0.2): Inherit from rust-num-rational-0.3.

gnu/packages/crates-io.scm

@@ -14833,8 +14833,36 @@ (define-public rust-num-iter-0.1
     (license (list license:asl2.0
                    license:expat))))
 
+(define-public rust-num-rational-0.3
+  (package
+    (name "rust-num-rational")
+    (version "0.3.0")
+    (source
+      (origin
+        (method url-fetch)
+        (uri (crate-uri "num-rational" version))
+        (file-name
+         (string-append name "-" version ".tar.gz"))
+        (sha256
+         (base32
+          "0f41j1l1kn5jj36a8xdy8kv242wlwq0ka578vm8gnb1n1wvdgd55"))))
+    (build-system cargo-build-system)
+    (arguments
+     `(#:cargo-inputs
+       (("rust-num-bigint" ,rust-num-bigint-0.3)
+        ("rust-num-integer" ,rust-num-integer-0.1)
+        ("rust-num-traits" ,rust-num-traits-0.2)
+        ("rust-serde" ,rust-serde-1.0)
+        ("rust-autocfg" ,rust-autocfg-1.0))))
+    (home-page "https://github.com/rust-num/num-rational")
+    (synopsis "Rational numbers implementation for Rust")
+    (description
+     "Rational numbers implementation for Rust.")
+    (license (list license:expat license:asl2.0))))
+
 (define-public rust-num-rational-0.2
   (package
+    (inherit rust-num-rational-0.3)
     (name "rust-num-rational")
     (version "0.2.3")
     (source
@@ -14846,19 +14874,13 @@ (define-public rust-num-rational-0.2
        (sha256
         (base32
          "18q3vq3xldhaj0z3f92am8f59m1awywgdj28c7wvx0bcksgwfkfs"))))
-    (build-system cargo-build-system)
     (arguments
      `(#:cargo-inputs
        (("rust-num-bigint" ,rust-num-bigint-0.2)
         ("rust-num-integer" ,rust-num-integer-0.1)
         ("rust-num-traits" ,rust-num-traits-0.2)
         ("rust-serde" ,rust-serde-1.0)
-        ("rust-autocfg" ,rust-autocfg-1.0))))
+        ("rust-autocfg" ,rust-autocfg-1.0))))))
-    (home-page "https://github.com/rust-num/num-rational")
-    (synopsis "Rational numbers implementation for Rust")
-    (description
-     "Rational numbers implementation for Rust.")
-    (license (list license:expat license:asl2.0))))
 
 (define-public rust-num-rational-0.1
   (package