Fix some log table styling.

Refresh user list on start-up and schedule refresh every 12 hours.
Handle malformed lines when reading Plex logs slightly more gracefully.
Send back empty list instead of None on some plex.tv requests.

data/interfaces/default/js/tables/plex_logs.js

@@ -19,11 +19,13 @@ var plex_log_table_options = {
     "columnDefs": [
         {
             "targets": [0],
-            "width": "15%"
+            "width": "15%",
+            "className": "no-wrap"
         },
         {
             "targets": [1],
-            "width": "10%"
+            "width": "10%",
+            "className": "no-wrap"
         },
         {
             "targets": [2],