Revert "demo_FEAbrick.cpp was added to the FEA demos."
Revert "demo_FEAbrick.cpp was added to the FEA demos."

This reverts commit 76af89d6ab3628868f346b76c14c38c4c2fedc35.

Bryan-Peterson/chrono,andrewseidl/chrono,amelmquist/chrono,dariomangoni/chrono,Bryan-Peterson/chrono,amelmquist/chrono,projectchrono/chrono,amelmquist/chrono,Bryan-Peterson/chrono,Milad-Rakhsha/chrono,rserban/chrono,projectchrono/chrono,armanpazouki/chrono,rserban/chrono,projectchrono/chrono,Milad-Rakhsha/chrono,rserban/chrono,amelmquist/chrono,dariomangoni/chrono,tjolsen/chrono,dariomangoni/chrono,armanpazouki/chrono,armanpazouki/chrono,tjolsen/chrono,Milad-Rakhsha/chrono,jcmadsen/chrono,projectchrono/chrono,jcmadsen/chrono,rserban/chrono,jcmadsen/chrono,jcmadsen/chrono,armanpazouki/chrono,tjolsen/chrono,tjolsen/chrono,andrewseidl/chrono,dariomangoni/chrono,dariomangoni/chrono,projectchrono/chrono,andrewseidl/chrono,rserban/chrono,amelmquist/chrono,Bryan-Peterson/chrono,amelmquist/chrono,andrewseidl/chrono,Milad-Rakhsha/chrono,armanpazouki/chrono,andrewseidl/chrono,armanpazouki/chrono,tjolsen/chrono,dariomangoni/chrono,rserban/chrono,Milad-Rakhsha/chrono,projectchrono/chrono,Bryan-Peterson/chrono,jcmadsen/chrono,Milad-Rakhsha/chrono,rserban/chrono,jcmadsen/chrono,jcmadsen/chrono