LiquidCrystalElastomer test

[tupek2]

The first iteration of this test does not converge. Any change in solver behavior breaks this test. Is this model still needed, is it well formulated (I suspect nonsmoothness, but I cannot be sure)?

[btalamini]

@barreracruz , is this model still useful to you? The test is meant to keep it fresh and make sure we don't break it. We're happy to continue to do so if you still need it.

[barreracruz]

After chatting with @tupek2 , we agreed to keep the model for now since the test passes now. Apologies for the delay. Didn't have access to GitHub until today :)