SRFWallVelocityFvPatchVectorField: New BC for walls rotating in the SRF

    Wall-velocity condition to be used in conjunction with the single rotating
    frame (SRF) model (see: FOAM::SRFModel)

    The condition applies the appropriate rotation transformation in time and
    space to determine the local SRF velocity of the wall.

        \f[
            U_p = - U_{p,srf}
        \f]

    where
    \vartable
        U_p     = patch velocity [m/s]
        U_{p,srf} = SRF velocity
    \endvartable

    The normal component of \f$ U_p \f$ is removed to ensure 0 wall-flux even
    if the wall patch faces are irregular.

    \heading Patch usage

    Example of the boundary condition specification:
    \verbatim
    myPatch
    {
        type            SRFWallVelocity;
        value           uniform (0 0 0);    // Initial value
    }
    \endverbatim