Adds UND undulator energy in keV

Load.py

@@ -58,7 +58,9 @@ mnemonics = {
     "navitar": {'source':'SCS_XTD10_IMGES/CAM/BEAMVIEW_NAVITAR:daqOutput',
                'key':'data.image.pixels',
                'dim':['x','y']},
-
+    "UND": {'source':'SA3_XTD10_UND/DOOCS/PHOTON_ENERGY',
+                'key':'actualPosition.value',
+                'dim':None},
     # XTD10 XGM
     ## keithley
     "XTD10_photonFlux": {'source':'SA3_XTD10_XGM/XGM/DOOCS',