Stokes

- The equations I started with for stokes are wrong
- Refer to http://www.dealii.org/developer/doxygen/deal.II/step_22.html for a test case we might implement and compare. 
- The deal.ii package was developed over 10+ years. We wont hope to compare in functionality, but we can definitely borrow their logic for solving PDEs and substitute RBF-FD as the numerical method. 
