code: function updateBowerVersion () {
      start('Updating bower version...');
      const options = { cwd: './bower-material' };
      const bower   = require(options.cwd + '/bower.json'),
            pkg     = require(options.cwd + '/package.json');
      // update versions in config files
      bower.version = pkg.version = newVersion;
      fs.writeFileSync(options.cwd + '/package.json', JSON.stringify(pkg, null, 2));
      fs.writeFileSync(options.cwd + '/bower.json', JSON.stringify(bower, null, 2));
      done();
      start('Building bower files...');
      // build files for bower
      exec([
        'rm -rf dist',
        'gulp build',
        'gulp build-all-modules --mode=default',
        'gulp build-all-modules --mode=closure',
        'rm -rf dist/demos'
       ]);
      done();
      start('Copy files into bower repo...');
      // copy files over to bower repo
      exec([
             'cp -Rf ../dist/* ./',
             'git add -A',
             `git commit -m "release: version ${newVersion}"`,
             'rm -rf ../dist'
           ], options);
      done();
      // add steps to push script
      pushCmds.push(
        comment('push to bower (master and tag) and publish to npm'),
        'cd ' + options.cwd,
        'cp ../CHANGELOG.md .',
        'git add CHANGELOG.md',
        'git commit --amend --no-edit',
        `git tag -f v${newVersion}`,
        'git pull --rebase --strategy=ours',
        'git push',
        'git push --tags',
        'rm -rf .git/',
        'npm publish',
        'cd ..'
      );
    }
docs: updates the version for bower-material in package.json and bower.json