Merge pull request #1 from sinanuozdemir/master

Update 04_Neural_Networks.ipynb

started graphical models

bug fix in decision_trees

updated decision trees

added pysrc for Neural Network, started including work by Mitchel

updates to Neural networks

initial work on neural networks

added discriminative logistic regression example

upgraded to Ipython 0.13, initial commit of 03_Linear_Classification - which is not done

added pysrc for those without ipython notebook

added Bayesian approach to linear regression

updated intro, better sectioning of frequentist and Bayesian in Regression

updates to introduction, added readings list

Update master