Ported WCNN. Documentation is still missing

bob/learn/linear/__init__.py

bob/learn/linear/cpp/wccn.cpp

bob/learn/linear/include/bob.learn.linear/api.h

bob/learn/linear/include/bob.learn.linear/wccn.h

bob/learn/linear/main.cpp

bob/learn/linear/test.py

bob/learn/linear/wccn.cpp

bob/learn/linear/wccn.py

setup.py