Add participant ID

Collect participant ID at the beginning, store in database, export with
results.  Closes https://github.com/mattbk/changeblindness/issues/2.

views/index.html.twig

@@ -4,7 +4,12 @@
     <header class="hero-unit">
         <h1>Change blindness test</h1>
         <p>We would like a few minutes of your time to help us with a test in change blindness. Your help is very much appreciated.</p>
-        <p><a class="btn btn-primary btn-large" href="{{ start_url }}">Get started &raquo;</a></p>
+
+		<form action="{{ start_url }}" method="post">
+		Name: <input type="text" name="participantid">
+		<input type="submit" value="Start">
+		</form>
+
         <p><div class="fb-like" data-layout="button_count" data-width="450" data-show-faces="false" data-font="arial"></div></p>
         <p><a href="https://twitter.com/share" class="twitter-share-button" data-via="RaymondJelierse" data-hashtags="vcd">Tweet</a></p>
     </header>

views/results.html.twig

@@ -54,6 +54,7 @@
                 <th>uid</th>
                 <th>date</th>
                 <th>host</th>
+                <th>participant</th>
                 <th>phase</th>
                 <th>x</th>
                 <th>y</th>
@@ -67,6 +68,7 @@
                 <td>{{record.uid}}.</td>
                 <td>{{ record.datetime }}</td>
                 <td>{{ record.host }}</td>
+                <td>{{ record.participantid }}</td>                
                 <td>{{ record.phase }}</td>
                 <td>{{ record.xcoordinate }}</td>
                 <td>{{ record.ycoordinate }}</td>

views/results.txt.twig

@@ -1,4 +1,4 @@
-uid	datetime	host	phase	xcoordinate	ycoordinate	responsetime	score
+uid	datetime	host	participant	phase	xcoordinate	ycoordinate	responsetime	score
 {% for record in data %}
-{{record.uid}}	{{record.datetime}}	{{record.host}}	{{record.phase}}	{{record.xcoordinate}}	{{record.ycoordinate}}	{{record.responsetime}}	{{record.score}}
+{{record.uid}}	{{record.datetime}}	{{record.host}}	{{record.participantid}}	{{record.phase}}	{{record.xcoordinate}}	{{record.ycoordinate}}	{{record.responsetime}}	{{record.score}}
 {% endfor %}