switch to vndr

vndr is almost exactly the same as our old good hack/vendor.sh. Except
it's cleaner and it allows to re-vendor just one dependency if needed
(which we do a lot for containers/image).

Signed-off-by: Antonio Murdaca <runcom@redhat.com>

vendor/github.com/opencontainers/runc/NOTICE

@@ -0,0 +1,17 @@
+runc
+
+Copyright 2012-2015 Docker, Inc.
+
+This product includes software developed at Docker, Inc. (http://www.docker.com).
+
+The following is courtesy of our legal counsel:
+
+
+Use and transfer of Docker may be subject to certain restrictions by the
+United States and other governments.  
+It is your responsibility to ensure that your use and/or transfer does not
+violate applicable laws. 
+
+For more information, please see http://www.bis.doc.gov
+
+See also http://www.apache.org/dev/crypto.html and/or seek legal counsel.