Be able to move bodies with a specified velocity function

[aharwood2]

It would be a useful feature to be able to move / rotate IBM structures with a given velocity function. The IBM code would need an upgrade to allow this feature.

[Akarshr1234]

Hi,
I need to rotate an airfoil in a sinasoidal fashion. So, can you suggest what upgrade is required for it.

[ianhinder]

I have added some suggestions in #17.