Adding new property method attributes to lattice classes.
Adding new property method attributes to lattice classes.

Adding the following new property method attributes to
the `Crystal2DLattice`, `Reciprocal2DLattice`,
`Crystal3DLattice`, and `Reciprocal3DLattice` classes:

* `lengths`
* `angles`
* `lengths_and_angles`
* `lattice_parameters`
* `lattice_vectors`

scikit-nano/scikit-nano,scikit-nano/scikit-nano,androomerrill/scikit-nano,androomerrill/scikit-nano