add keywrap test vectors from NIST

From http://csrc.nist.gov/groups/STM/cavp/documents/mac/kwtestvectors.zip
diff --git a/docs/development/test-vectors.rst b/docs/development/test-vectors.rst
index d5e2751..ad6c60c 100644
--- a/docs/development/test-vectors.rst
+++ b/docs/development/test-vectors.rst
@@ -147,6 +147,11 @@
 * PBKDF2 (HMAC-SHA1) from :rfc:`6070`.
 * scrypt from the `draft RFC`_.
 
+Key wrapping
+~~~~~~~~~~~~
+
+* AES key wrap (AESKW) and 3DES key wrap test vectors from `NIST CAVP`_.
+
 Recipes
 ~~~~~~~