Updated full calendar to 1.6.4

Calendar/Upcoming now update on grab/download events
Better use of backbone collection on calendar
New: Calendar will auto refresh when episodes are grabbed and downloaded

src/UI/Content/Overrides/fullcalendar.less

@@ -0,0 +1,11 @@
+.fc-view {
+  overflow: visible;
+}
+
+.fc-event-title {
+  padding: 0 2px;
+  display: block;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+  overflow: hidden;
+}