[build] add script to train DCGAN in setup.py

setup.py

@@ -70,6 +70,7 @@ setup(
       # scripts should be declared using this entry:
       'console_scripts' : [
         'train_cnn.py = bob.learn.pytorch.scripts.train_cnn:main', 
+        'train_dcgan.py = bob.learn.pytorch.scripts.train_dcgan:main', 
       ],
    },