FEATURE: Full height hamburger menu

- Rename `site-map` to `hamburger-menu`
- Includes acceptance tests

test/javascripts/components/keyboard-shortcuts-test.js.es6

@@ -55,7 +55,7 @@ module("lib:keyboard-shortcuts", {
       "<div class='alert alert-info clickable'></div>",
       "<button id='create-topic'></button>",
       "<div id='user-notifications'></div>",
-      "<div id='site-map'></div>",
+      "<div id='toggle-hamburger-menu'></div>",
       "<div id='search-button'></div>",
       "<div id='current-user'></div>",
       "<div id='keyboard-help'></div>"