Smooth out oscillations during orbit targeting

[ChristopherRabotin]

With higher fidelity dynamics, orbital elements will start to oscillate. That causes issues with the orbital target control laws. For example, targeting SMA, ECC and INC at the same time even with only J2 will lead to problems with the targeting: the thrust angle will attempt to correct for these oscillations, when they really shouldn't try that.

One of the solution that Nathan P. has used successfully in the past in caching the oscillating OEs at the same point in the orbit will hide these oscillations.