Make scrolling message conditionally include information.

This fixes a number of Nonetype accessing bugs when things
are not present in the database. Have manually tested this for
now.

xppl/views.py

@@ -157,20 +157,33 @@ def uploaded_file_cover(filename):
 
 @app.route('/updates', methods=['POST', 'GET'])
 def get_updates():
-    userin = UserIns.query.filter_by(title="lastViewed").first()
     allbooks = db.session.query(Book).all()
-    latest_upload = allbooks[-1]
-    return (
-        "This is the XPPL ~ Library XPUB ~ Updates / / / / / / / Last viewed: "
-        + userin.info
-        + " / / / / / / / "
-        + str(len(allbooks))
-        + " Books online "
-        + " / / / / / / / "
-        + "Latest entry: "
-        + latest_upload.title
+
+    scrolling_message = (
+        '{domain} ~ XPPL ~ Updates'
+        ' / / / / / / / '
+        '{count} books online '
+    ).format(
+        domain=app.config['DOMAIN'],
+        count=str(len(allbooks))
     )
 
+    userin = UserIns.query.filter_by(title='lastViewed').first()
+    if userin:
+        scrolling_message += (
+            ' / / / / / / / '
+            ' Last viewed: {user}'
+        ).format(user=userin.info)
+
+    if allbooks:
+        latest_upload = allbooks[-1]
+        scrolling_message += (
+            ' / / / / / / / '
+            'Latest entry: {title}'
+        ).format(title=latest_upload.title)
+
+    return scrolling_message
+
 
 @app.route('/volumetric_catalog', methods=['GET'])
 def volumetric_catalog():