Feature: Fan momentum source fvOption based on fan curve

An fvOption that models a fan curve based momentum source.

• Calculates the flow rate through (automatically calculated) upstream faces of the cell zone
• Based on the flow rate, calculates the pressure gradient from the provided fan pressure curve and the thickness of the fan
• Adds the calculated pressure gradient momentum source to the equation

Example dictionary input:

fanModel
{
    type          fanMomentumSource;
    active        on;
    selectionMode cellZone;
    cellZone      fanCellZone;
    faceZone      fanSurroundingFaceZone;
    fanCurve
    {
        type table;
        file "constant/fanCurve";
    }
    fields    (U);
    flowDir   (1.0 0.0 0.0);
    thickness 0.2;
    rho       1;
}

Question: We have a small validation case of a flow through a pipe with a fan, that takes roughly 1 minute to calculate locally (for me). Would it be appropriate to add it to tutorials so that it's covered by Alltest script? Also, we have a small python script for asserting the calculated pressure gradient after the simulation finishes. Would it be ok to add that as well and make this run in your pipeline?