functionObjects::icoUncoupledKinematicCloud: tracks a uncoupled kinematic particle cloud

Description
    This Foam::functionObject tracks a uncoupled kinematic particle cloud in the
    specified velocity field of an incompressible flow (laminar, RANS or LES).

    It may be used in conjunction with any transient single-phase incompressible
    flow solver such as \c pisoFoam or \c pimpleFoam and tracks the particles or
    parcels without affecting the the flow-field.

    The \c kinematicCloud requires the the density of the fluid which is
    looked-up from \c constant/transportProperties dictionary and the
    acceleration due to gravity which is read from the \c constant/g file if
    present or defaults to zero.

    The \c kinematicCloud properties are read from the \c
    constant/kinematicCloudProperties dictionary in the usual manner.

    Example of function object specification:
    \verbatim
        tracks
        {
            libs ("liblagrangianFunctionObjects.so");
            type icoUncoupledKinematicCloud;
        }
    \endverbatim

    \heading Function object usage
    \table
        Property | Description                     | Required   | Default value
        type     | Type name: icoUncoupledKinematicCloud | yes  |
        U        | Name of the velocity field       | no        | U
        kinematicCloud | Name of the kinematicCloud | no        | kinematicCloud
    \endtable