Revert "Added ElasticDeltaV method, as well as physics and soft body classes"

This reverts commit 9fae47b01ee96140d32e153e7127ee5fced17f78.
Revert "Revert "Added ElasticDeltaV method, as well as physics and soft body classes""

This reverts commit 943a794a9e71bbd9cf72a70b6087ea470374d888.
Revert "Revert "Revert "Added ElasticDeltaV method, as well as physics and soft body classes"""

This reverts commit 30a59e1c79fc37e79d3aaf81cc43fc010a1a93b5.