Extract volumetric function from neo-hooke

created branch 99-extract-volumetric-function-from-neo-hooke to address this issue

By jonathan.froehlich on 2021-12-01T13:16:21 (imported from GitLab)

mentioned in merge request !114 (merged)

By jonathan.froehlich on 2021-12-01T17:55:36 (imported from GitLab)

closed

mentioned in commit 911e6414

By jonathan.froehlich on 2021-12-01T18:27:21 (imported from GitLab)