updated geometry and physics models to use get_pore/throat_locations
Merge branch 'feature/locations' of https://github.com/PMEAL/OpenPNM into feature/locations

Conflicts:
	OpenPNM/Physics/capillary_pressure.py
	OpenPNM/Physics/diffusive_conductance.py
Added pores() and throats() methods to GenericNetwork and GenericGeometry
- These methods are meant to simplify the process of retrieving pores and throats
MAJOR CHANGES
- geometry now has a pores and a throats property
- all geometry models have been updated
- a new setter/getter has been added to Tools, called set_data/get_data.  Instead of locations it takes pores or throats as an argument
- I think this spells the end of the term location, as it is very confusing and not needed now.
GenericGeometry no longer accepts locations during initialization