Camera parameters should be float instead of int (return of pyflex.get_camera_params)

Hello developers! Thank you very much for the active developments!

Since the camera parameters (position & rotation) are float, I think these lines are buggy, https://github.com/Xingyu-Lin/softgym/blob/bb383f64cd488062587714abbae38f27ed9f2457/PyFlex/bindings/pyflex.cpp#L840-L854

So, the return should be py::array_t<float> instead of py::array_t<int>?

Thanks!