add pyephem to dependencies

Author: wholmgren

setup.py

@@ -35,14 +35,12 @@
                          'pandas >= 0.15',
                          'pytz',
                          'six',
+                         'pyephem',
                          ],
     'scripts': [],
     'include_package_data': True
 }
 
-# more packages that we should consider requiring:
-# 'pyephem',
-
 # set up pvlib packages to be installed and extensions to be compiled
 PACKAGES = ['pvlib']