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   Calculates orbital elements for an in-line formation.
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   Form:
   elSet = ProjLine( aRef, iRef, kSats, rF ) 
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   Inputs
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   aRef           (1)     semi-major axis of reference orbit [km]
   iRef           (1)     inclination of reference orbit [rad]
   kSats          (1)     number of satellites
   rF             (1)     distance between satellites [km]

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   Outputs
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   elSet         (kSats,6)     Orbital elements of all spacecraft
   rH            (3,kSats)     Radius vector in Hills frame   [km]
   vH            (3,kSats)     Velocity vector in Hills frame [km/s]

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