Remove C++ code and build dependencies.

bob/learn/em/__init__.py

bob/learn/em/cpp/EMPCATrainer.cpp

bob/learn/em/cpp/FABase.cpp

bob/learn/em/cpp/FABaseTrainer.cpp

bob/learn/em/cpp/GMMBaseTrainer.cpp

bob/learn/em/cpp/GMMMachine.cpp

bob/learn/em/cpp/GMMStats.cpp

bob/learn/em/cpp/Gaussian.cpp

bob/learn/em/cpp/ISVBase.cpp

bob/learn/em/cpp/ISVMachine.cpp

bob/learn/em/cpp/ISVTrainer.cpp

bob/learn/em/cpp/IVectorMachine.cpp

bob/learn/em/cpp/IVectorTrainer.cpp

bob/learn/em/cpp/JFABase.cpp

bob/learn/em/cpp/JFAMachine.cpp

bob/learn/em/cpp/JFATrainer.cpp

bob/learn/em/cpp/KMeansMachine.cpp

bob/learn/em/cpp/KMeansTrainer.cpp

bob/learn/em/cpp/LinearScoring.cpp

bob/learn/em/cpp/MAP_GMMTrainer.cpp