VTK wind file reading for InflowWind

[andrew-platt]

Is your feature request related to a problem? Please describe.
Sometimes it would be useful to use VTK wind files in OpenFAST. This is currently not possible outside of FAST.Farm since InflowWind cannot read this format natively.

Describe the solution you'd like
Add an option and file handling to import VTK wind files, both 3D and 4D, into the InflowWind file parsing. The FlowField data structure in theory supports the 4D data format, so this should be just a file reading and data parsing issue.

Describe alternatives you've considered
It is possible to run FAST.Farm with a single turbine and VTK wind inputs.

Additional context
This idea came up while attempting to model a turbulent wind field with a wind direction change.

One alternative (or maybe supplemental) approach is to allow for a file input for the PropagationDir and rotate a turbulent wind field during the simulation. There may be some complications with this though (LiDAR would not work correctly).