code: function tightenDependenciesVersions(grunt, deps) {
    console.assert(deps, 'missing deps object');
    Object.keys(deps).forEach(function (name) {
      var version = deps[name];
      warnOnLooseVersion(grunt, name, version);
      version = tightenVersion(version);
      deps[name] = version;
    });
  }
docs: removes ~, ^, etc from dependencies versions