Remove all frameworks except Bootstrap (#251)

- Remove all frameworks except Bootstrap

- Remove roots-options.php and replace with a more simple
  roots-config.php

- Include all Bootstrap Javascript plugins by default in
  js/plugins.js

- Use Bootstrap Responsive and Topbar navigation by default

- Use Bootstrap markup on forms, page titles, image galleries,
  alerts and errors, post and comment navigation

- Remove Roots styles from style.css and introduce app.css for
  site-specific CSS. Remove almost all previous default Roots
  styles.

- Add latest updates from H5BP project

inc/roots-config.php

@@ -0,0 +1,12 @@
+<?php
+
+define('POST_EXCERPT_LENGTH',  40);
+define('BOOTSTRAP_RESPONSIVE', true);
+define('WRAP_CLASSES',         'container');
+define('CONTAINER_CLASSES',    'row');
+define('MAIN_CLASSES',         'span8');
+define('SIDEBAR_CLASSES',      'span4');
+define('FULLWIDTH_CLASSES',    'span12');
+define('GOOGLE_ANALYTICS_ID',  '');
+
+?>