Add PART:COP, PART:COL, VESSEL:COM, VESSEL:COP and VESSEL:COL (and ELEMENT) suffixes

[Earth-And-Moon]

The PART:COM suffix was added in 1.5.1.0 to get the center of mass for individual parts. KSP's Part class also has suffixes for CoPOffset and CoLOffset for center of pressure and center of lift. It would be useful to expose these suffixes as well for more advanced aerodynamical calculations and for consistency. This would only involve copying PartValue's GetCoM() function and the CoM suffix with few changes. The Vessel class also exposes these suffixes (for the whole vessel), so those could be exposed as well.