Have plotly calculate some margins

Framework/PythonInterface/plugins/algorithms/WorkflowAlgorithms/SavePlot1D.py

@@ -150,7 +150,7 @@ class SavePlot1D(mantid.api.PythonAlgorithm):
                 fig['layout']['yaxis%d' % (i+1)].update(title=ylabel)
                 if len(spectraNames) > 0:  # remove the used spectra names
                     spectraNames = spectraNames[len(traces):]
-            fig['layout'].update(margin={'l':40,'r':0,'t':0,'b':40})
+            fig['layout'].update(margin={'r':0,'t':0})
         else:
             (traces, xlabel, ylabel) = self.toScatterAndLabels(self._wksp,
                                                                spectraNames)