Reduced memory consumption of BayesNet by clearing out m_Instances at the end of buildClassifier.

git-svn-id: https://svn.cms.waikato.ac.nz/svn/weka@10378 e0a1b77d-ad91-4216-81b1-defd5f83fa92
Committed patch by Rosjier Lammers: reweighting term is now just computed once.

git-svn-id: https://svn.cms.waikato.ac.nz/svn/weka@10379 e0a1b77d-ad91-4216-81b1-defd5f83fa92
Reduced memory consumption of BayesNet by clearing out m_Instances at the end of buildClassifier.

git-svn-id: https://svn.cms.waikato.ac.nz/svn/weka@10380 e0a1b77d-ad91-4216-81b1-defd5f83fa92