Fixed bugs introduced while converting from Python to C++

[jasseeeem]

While testing OCSort C++ code base, I noticed that few variables were not matching. On digging deeper, I found couple of bugs in the C++ code after comparing to Python code.

1. A comma is given instead of multiplication operator resulting in the second operand F.transpose() being returned instead of (F * P) * F.transpose():
   Python code:
   P = (alpha * alpha) * dot(dot(F, P), F.T) + Q
   Incorrect C++ code:
   P = _alpha_sq * ((F * P), F.transpose()) + Q;
   Correct C++ code:
   P = _alpha_sq * ((F * P) * F.transpose()) + Q;

2. Added an inverse operation that was present in the Python code, but not in the C++ code.

Note: There is no change in line 1 and 156.

[jasseeeem]

Hey @noahcao
Can we merge this?

[jasseeeem]

Hey @noahcao
Please take a look!