ENH: functionObject: refactored co-ordinate system usage and new forceCoeffs members

If applied: This commit on top of the current forceCoeffs allows the user to compute:

• Side force coefficient whose direction in curl(lift,drag),
• Yaw moment coefficient whose rotation axis in dir(lift),
• Roll moment coefficient whose rotation axis in dir(drag)
• Also, for developers:
  • Destructor is = default
  • Some divisions were replaced by multiplications
  • Some repetitive multiplications were reduced to a single oper
  • Name change: momentCoeff -> pitchMomentCoeff
  • Order of output is reorganised as moments(pitch,yaw,roll) and forces(lift,drag,side)
  • For force coefs, the front and rear axles' contributions are computed

Verification: Passed sanity checks and valgrind-memcheck

What's next:

• Update for the Extended code guide entry

Related:

• Designated pitch, yaw, roll orientation can be seen in: en.wikipedia.org/wiki/Yaw_(rotation)#/media/File:Flight_dynamics_with_text.png