Fix modulator (see a49aa116)

pykat/components.py

@@ -1490,8 +1490,9 @@ class modulator(Component):
     def order(self, value):
 
         try:
-            value = int(value)
-
+            value = float(value)
+            if not value.is_integer():
+                raise pkex.BasePyKatException("modulator order must be an integer between 1 and 6 or 's' for single sideband")
             if value <= 1 and value > 6:
                 raise pkex.BasePyKatException("modulator order must be between 1 and 6 or 's' for single sideband")