CLIMATE-285, 286 - Add BinaryMetric base class. Remove __init__ from UnaryMetric base class.
CLIMATE-285, 286 - Add BinaryMetric base class. Remove __init__ from UnaryMetric base class.

git-svn-id: https://svn.apache.org/repos/asf/incubator/climate/trunk@1521536 13f79535-47bb-0310-9956-ffa450edef68

Former-commit-id: 17016ebc921969b4d9e18a7e147af7b2436d3142
riverma/climate,MBoustani/climate,MJJoyce/climate,kwhitehall/climate,MBoustani/climate,lewismc/climate,MBoustani/climate,pwcberry/climate,lewismc/climate,pwcberry/climate,kwhitehall/climate,apache/climate,pwcberry/climate,riverma/climate,huikyole/climate,huikyole/climate,apache/climate,MBoustani/climate,lewismc/climate,Omkar20895/climate,riverma/climate,MJJoyce/climate,agoodm/climate,riverma/climate,agoodm/climate,apache/climate,MJJoyce/climate,lewismc/climate,pwcberry/climate,huikyole/climate,MBoustani/climate,agoodm/climate,jarifibrahim/climate,jarifibrahim/climate,jarifibrahim/climate,Omkar20895/climate,apache/climate,MJJoyce/climate,Omkar20895/climate,jarifibrahim/climate,agoodm/climate,jarifibrahim/climate,Omkar20895/climate,MJJoyce/climate,apache/climate,riverma/climate,lewismc/climate,huikyole/climate,Omkar20895/climate,kwhitehall/climate,pwcberry/climate,huikyole/climate,agoodm/climate,kwhitehall/climate