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

css/app.css

@@ -0,0 +1,100 @@
+/* =============================================================================
+   Base
+   ========================================================================== */
+
+body { }
+
+
+
+/* =============================================================================
+   Header
+   ========================================================================== */
+
+#banner { }
+
+/* Fixed Topbar Navigation */
+body { padding-top: 60px; }
+body.admin-bar .navbar-fixed-top { top: 28px; }
+
+
+
+/* =============================================================================
+   Content
+   ========================================================================== */
+
+#content { }
+
+
+
+/* =============================================================================
+   Primary Content
+   ========================================================================== */
+
+#main { }
+
+
+
+/* =============================================================================
+   Sidebar
+   ========================================================================== */
+
+#sidebar { }
+
+
+
+/* =============================================================================
+   Posts
+   ========================================================================== */
+
+.hentry header { }
+.hentry h2 a { text-decoration: none; }
+.hentry time { display: block; }
+.hentry p.byline { }
+.hentry footer { clear: both; }
+
+
+
+/* =============================================================================
+   Post Comments
+   ========================================================================== */
+
+#comments, #respond, #submit { clear: both; display: block; }
+ol.commentlist img.avatar { float: left; margin-right: 10px; }
+
+
+
+/* =============================================================================
+   Footer
+   ========================================================================== */
+
+#content-info {
+  margin-top: 45px;
+  padding: 35px 0 36px;
+  border-top: 1px solid #e5e5e5;
+}
+
+#content-info p small { font-size: 13px; }
+
+
+
+/* =============================================================================
+   WordPress Generated Classes
+   See: http://codex.wordpress.org/CSS#WordPress_Generated_Classes
+   ========================================================================== */
+
+.aligncenter { display: block; margin: 0 auto; }
+.alignleft { margin: 0 20px 20px 0; float: left; }
+.alignright { margin: 0 0 20px 20px; float: right; }
+
+
+
+/* =============================================================================
+   Media Queries
+   ========================================================================== */
+
+@media (max-width: 980px) {
+  /* Fix top padding when using the responsive grid with the fixed topbar */
+  body {
+    padding-top: 0;
+  }
+}