A11y fixes for pa11y dashboard pages. (#306)

* First draft of a11y fixes.

* Amended results title

* Amended results title (again)

* Back to top keyboard operation

Removed the 'data-role="top"' attribute, which implemented a cool animation to scroll to top but prevented the default behaviour, resulting in the keyboard focus not going back to top.

* Options Button

Fix to have a working options button, but using the mouse only. This is not a good solution because it cannot be operated via the keyboard.

* Fixed options menu css.

* Results view layout changes

* Undoing layout changes

* Graph layout fixes.

* Skip Rules Link

Added a link to skip the list of rules, which can get very long and annoying for any keyboard user not interested in selecting a rule. Most probably, implementing a collapsible list of rules would be a better solution here.

Co-authored-by: Carlos Muncharaz <carlos@muncharaz.eu>

view/partial/breadcrumb.html

@@ -15,16 +15,17 @@ You should have received a copy of the GNU General Public License
 along with Pa11y Dashboard.  If not, see <http://www.gnu.org/licenses/>.
 }}
 {{#unless isHomePage}}
-	<div class="container">
+	<nav class="container" aria-labelledby="breadcrumb">
 		<div class="row">
 			<div class="col-md-12">
+				<h2 id="breadcrumb" class="sr-only">Breadcrumb Navigation</h2>
 				<ol class="breadcrumb">
 					<li><a href="/">Dashboard</a></li>
 					{{#if isNewTaskPage}}
 						<li class="active">Add URL</li>
 					{{/if}}
 					{{#if isTaskPage}}
-					  <li class="active">{{task.name}}</li>
+					<li class="active">{{task.name}}</li>
 					{{/if}}
 					{{#if isTaskSubPage}}
 						<li><a href="{{task.href}}">{{task.name}}</a></li>
@@ -36,5 +37,5 @@ along with Pa11y Dashboard.  If not, see <http://www.gnu.org/licenses/>.
 				</ol>
 			</div>
 		</div>
-	</div>
+	</nav>
 {{/unless}}