Bugfix for legacy files without "Power Track" attribute

fepydas/constructors/datareaders/FromLabview.py

@@ -111,7 +111,7 @@ def Automatic(filename):
       if headers["Measurement Type"][1] == "PLE Xe Arc Lamp":
         return PLE(axis,keys,values,None,None,headers)
       else:
-        if headers["Power Track"][0] == "Record" or headers["Power Track"][0] == "Correct":
+        if "Power Track" in headers.keys() and (headers["Power Track"][0] == "Record" or headers["Power Track"][0] == "Correct"):
           powers = Data1D(numpy.array(units[2+values.values.shape[0]:2+2*values.values.shape[0]]).astype(numpy.float64),DataType("Power","mW"))
         else:
           powers = None