Fix bugs (minor typos)

Fix bugs (minor typos)

Prior to this merge:

• Incorrect UUID was being stored in completed list.
• save_text was being called in the save_plot 0MQ API method.

As of this commit, both of these issues are fixed.

dstat_interface/plugin.py

@@ -117,10 +117,10 @@ class DstatPlugin(ZmqPlugin):
         Args
         ----
 
-            save_plot_path (str) : Path to file to save text data.
+            save_plot_path (str) : Path to file to save plot.
         '''
         data = decode_content_data(request)
-        save_text(self.parent.current_exp, data['save_plot_path'])
+        save_plot(self.parent.current_exp, data['save_plot_path'])
 
     def on_execute__acquisition_complete(self, request):
         '''