v0    = initial conditions
n     = number of differential equations
m     = number of controling equations
lthrst= 0 starting proceedure in subroutine nint
uses zero initial guess at higher derivatives
of approximating polynomial
lthrst= 1 starting proceedure uses current value of these
derivatives (set in subroutine sbout for starting
proceedure at initiation and termination of les-8/9
station keeping thrusts)