gnu: Add rust-ndarray-0.13.

* gnu/packages/crates-io.scm (rust-ndarray-0.13): New variable.
(rust-ndarray-0.12): Inherit from above.
* gnu/packages/patches/rust-ndarray-0.13-remove-blas-src.patch: New file.
* gnu/local.mk: Register new file.

gnu/packages/patches/rust-ndarray-0.13-remove-blas-src.patch

@@ -0,0 +1,28 @@
+ Cargo.toml | 6 +-----
+ 1 file changed, 1 insertion(+), 5 deletions(-)
+
+diff --git a/Cargo.toml b/Cargo.toml
+index 1f3e1b6..36bc816 100644
+--- a/Cargo.toml
++++ b/Cargo.toml
+@@ -43,11 +43,6 @@
+ version = "0.3.2"
+ optional = true
+ 
+-[dependencies.blas-src]
+-version = "0.2.0"
+-optional = true
+-default-features = false
+-
+ [dependencies.cblas-sys]
+ version = "0.1.4"
+ optional = true
+@@ -91,7 +86,7 @@
+ default-features = false
+ 
+ [features]
+-blas = ["cblas-sys", "blas-src"]
++blas = ["cblas-sys"]
+ docs = ["approx", "serde", "rayon"]
+ serde-1 = ["serde"]
+ test = ["test-blas-openblas-sys"]