Update metadata

Author: wooorm

package.json

@@ -8,5 +8,10 @@
     "type": "git",
     "url": "https://github.com/wooorm/mdast.git"
   },
-  "author": "Titus Wormer <tituswormer@gmail.com>"
+  "bugs": "https://github.com/wooorm/mdast/issues",
+  "author": "Titus Wormer <tituswormer@gmail.com> (http://wooorm.com)",
+  "contributors": [
+    "Titus Wormer <tituswormer@gmail.com> (http://wooorm.com)",
+    "Eugene Sharygin <eush77@gmail.com>"
+  ]
 }