code: function mkSrc(p) {
      var src = {};
      if (typeof p.inject === 'string') { src.async = p.inject; }
      src.path = fspath.extname(p.route) ?
                 p.route :
                 ppath.join(p.route || '/', fspath.basename(p.path));
      return src;
    }
docs: computes script src path from p.route + p.path returns object { path: async: }