add pkg-desc' and pkg-authors' to each package

This information will be used to construct a catalog from the
package directories.

original commit: 057bfc2ea1a24e85ece2d5f85da30076643ea598

pkgs/datalog/info.rkt

@@ -9,3 +9,7 @@
                "parser-tools-lib"))
 (define build-deps '("racket-doc"
                      "scribble-lib"))
+
+(define pkg-desc "An implementation of the Datalog language")
+
+(define pkg-authors '(jay))