adding requirements to setup file.

avoiding max pooling error when installing from source.

pyFTS/common/transformations/smoothing.py

@@ -1,7 +1,5 @@
 from pyFTS.common.transformations.transformation import Transformation 
 import numpy as np
-from math import ceil
-
 
 class MovingAverage(Transformation):
     def __init__(self, **kwargs):

setup.py

@@ -5,6 +5,10 @@ import setuptools
 
 setuptools.setup(
     name='pyFTS',
+    install_requires=[
+          'matplotlib',
+          'numpy',
+          'pandas'],
     packages=['pyFTS', 'pyFTS.benchmarks', 'pyFTS.common', 'pyFTS.common.transformations', 'pyFTS.data', 
               'pyFTS.models.ensemble', 'pyFTS.models', 'pyFTS.models.seasonal', 'pyFTS.partitioners', 
               'pyFTS.probabilistic', 'pyFTS.tests', 'pyFTS.models.nonstationary', 'pyFTS.models.multivariate',