Update tally

This pull requests finally puts tally objects as load-able and save-able objects to and from hdf5, similar to the existing material object capability. All comments welcome!
The reason this has been kept is it was in the example from the HDF5 group that I started with, the comment that was originally there basically said it was a safety thing, "Create the Compound datatype Because the standard types we are using for the file may have different sizes than the correseponding native types.....".