Added the changepoint model  and a  distribution to
Minor bugfix in DiscreteUniform
Draft of disaster_model; fix for slice sampler when sampling vector-valued variables
Improved Metropolis so that it accepts a mixture of discrete and continuous variables
simplified disaster model
Incorporated update to disaster_model from disasters branch
Pepified disaster_model
Improved annotation for disasters_model
Ensured upper and lower are ints for DiscreteUniform
Added distribution test for DiscreteUniform
Merge branch 'pymc3' of github.com:pymc-devs/pymc into pymc3

Conflicts:
	examples/hierarchical.py