parameters: remove unused logger

Change-Id: I2d51081c8e1f7315861c2280ceb92304327c2ac6

gnpy/core/parameters.py

@@ -9,7 +9,6 @@ This module contains all parameters to configure standard network elements.
 
 """
 
-from logging import getLogger
 from scipy.constants import c, pi
 from numpy import squeeze, log10, exp
 
@@ -18,9 +17,6 @@ from gnpy.core.utils import db2lin, convert_length
 from gnpy.core.exceptions import ParametersError
 
 
-logger = getLogger(__name__)
-
-
 class Parameters:
     def asdict(self):
         class_dict = self.__class__.__dict__