Added example with large elasto-plastic deformations

[lijas]

An example with large deformation plasticity. I basically copied the hyperelasticity problem but added an elasto-plastic material model.

Don't know if this example is needed since there already exists an example with plasticity.

Do you want the example to be in a ipynb-format? Can someone review the code to see where efficiency improvements can be made?

(I have no way in checking if the results is correct, but it looks reasonable in paraview.)

[lijas]

Do you know if there is a "solution" for the two issues i commented on above?

[termi-official]

Any plans on reviving this for the code gallery (or tutorials?)?