MorseDistanceModulator.py: improve a comment

Don't refer to "calls" anymore, MorseDistanceModulator is quite generic
and uses the period/pulse terminology.

Improve the grammar too...

diff --git a/src/savemysugar/MorseDistanceModulator.py b/src/savemysugar/MorseDistanceModulator.py
index 1f78382..fccd57f 100755 (executable)
--- a/src/savemysugar/MorseDistanceModulator.py
+++ b/src/savemysugar/MorseDistanceModulator.py
@@ -142,9 +142,9 @@ class MorseDistanceModulator(object):
 
         distances.append(self.symbol_to_distance("EOM"))
 
-        # Since the Morse signals are encoded in the distance between calls, an
-        # extra call is needed in order for receiver actually get the EOM and
-        # see that the transmission has terminated.
+        # Since the Morse symbols are encoded in the distance between periods,
+        # an extra pulse is needed in order for the receiver to actually get
+        # the EOM and see that the transmission has terminated.
         distances.append(0)
 
         return distances