chore: Renamed prepublish script to manpage

Author: phated

package.json

@@ -24,7 +24,7 @@
   ],
   "scripts": {
     "lint": "eslint .",
-    "prepublish": "marked-man --name gulp docs/CLI.md > gulp.1",
+    "manpage": "marked-man --name gulp docs/CLI.md > gulp.1",
     "pretest": "npm run lint",
     "test": "mocha --async-only --timeout 5000 test/lib test",
     "cover": "nyc mocha --async-only --timeout 5000 test/lib test"