Add two-way messaging view

> Once an inbound message has been received, there should be a way to
> see the other messages in the system from the same service to the same
> number. Both in and outbound. Nice inbox/whatsapp stylee view or some
> such. This way the context of the reply is understood.
>
> Initially will only see the outbound template, not the actual message,
> but we’re going to change this for the rest (soon), so that you can
> always see the full message for all outbound.

tests/app/main/views/test_conversation.py

@@ -0,0 +1,98 @@
+import pytest
+from bs4 import BeautifulSoup
+
+from flask import (
+    url_for,
+)
+from tests.conftest import (
+    SERVICE_ONE_ID,
+)
+from tests.app.test_utils import normalize_spaces
+from freezegun import freeze_time
+
+
+@pytest.mark.parametrize('index, expected', enumerate([
+    (
+        'message-8',
+        'Failed (sent yesterday at 2:59pm)',
+    ),
+    (
+        'message-7',
+        'Failed (sent yesterday at 2:59pm)',
+    ),
+    (
+        'message-6',
+        'Failed (sent yesterday at 4:59pm)',
+    ),
+    (
+        'message-5',
+        'Failed (sent yesterday at 6:59pm)',
+    ),
+    (
+        'message-4',
+        'Failed (sent yesterday at 8:59pm)',
+    ),
+    (
+        'message-3',
+        'Failed (sent yesterday at 10:59pm)',
+    ),
+    (
+        'message-2',
+        'Failed (sent yesterday at 10:59pm)',
+    ),
+    (
+        'message-1',
+        'Failed (sent yesterday at 11:00pm)',
+    ),
+    (
+        'template content',
+        'yesterday at midnight',
+    ),
+    (
+        'template content',
+        'yesterday at midnight',
+    ),
+    (
+        'template content',
+        'yesterday at midnight',
+    ),
+    (
+        'template content',
+        'yesterday at midnight',
+    ),
+    (
+        'template content',
+        'yesterday at midnight',
+    ),
+]))
+@freeze_time("2012-01-01 00:00:00")
+def test_view_conversation(
+    logged_in_client,
+    fake_uuid,
+    mock_get_notification,
+    mock_get_inbound_sms,
+    mock_get_notifications,
+    index,
+    expected,
+):
+
+    print(index)
+
+    response = logged_in_client.get(url_for(
+        'main.conversation',
+        service_id=SERVICE_ONE_ID,
+        notification_id=fake_uuid,
+    ))
+    assert response.status_code == 200
+    page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')
+
+    messages = page.select('.sms-message-wrapper')
+    statuses = page.select('.sms-message-status')
+
+    for elements in (messages, statuses):
+        assert len(elements) == 13
+
+    assert (
+        normalize_spaces(messages[index].text),
+        normalize_spaces(statuses[index].text),
+    ) == expected