Added different number of samples for quadratic time MMD
fix include config.h in SGRefObject
fix null spectrum approximation formula in quadratic time MMD
pca ipython notebook revised 3rd time
Merge pull request #2022 from lambday/develop

Added different number of samples for quadratic time MMD
Merge pull request #2028 from kislayabhi/develop

pca ipython notebook revised 3rd iteration
basic neural networks
small bugfix
small bugfix
fixed indents
fixed indents
removed unnecessary includes and typedefs
removed some unnecessary stuff
removed some more unnecessary stuff
made CNeuralNetwork inherit from CMachine
small modification to the python notebook