Merge branch 'staging' of git://github.com/elliottbiondo/pyne into elliottbiondo-staging
Added mass_density() and number_density() functions to C++ Material class.
Added cython bindings for mass_density() and number_density()
Added some tests for mass and number density
updated and cleaned up test for dens
Merge branch 'staging' of git://github.com/elliottbiondo/pyne into elliottbiondo-staging
Merge pull request #103 from scopatz/dens

New C++ Material density functions.
small bug fix in read_mcnp_inp