Accounting stats only shown if paused

Gah! Stupid me. Inverted a conditional, causing the accounting stats to not
show up until the interface is paused. Caught thanks to torix on tor-relays@...

  https://lists.torproject.org/pipermail/tor-relays/2017-November/013484.html

nyx/panel/graph.py

@@ -462,7 +462,7 @@ class GraphPanel(nyx.panel.Panel):
       return 0
 
     height = DEFAULT_CONTENT_HEIGHT + self._graph_height
-    accounting_stats = self._accounting_stats if nyx_interface().is_paused() else self._accounting_stats_paused
+    accounting_stats = self._accounting_stats if not nyx_interface().is_paused() else self._accounting_stats_paused
 
     if self._displayed_stat == GraphStat.BANDWIDTH and accounting_stats:
       height += 3