Update

Commented out  int main(){...} in BasicDrawingTest.cpp to enable
googletest.

Added
Coordinate::operator+(...),
VectorQuantity::getMagnitude(...),
VectorQuantity::getAngle(...) and
VectorQuantity::getCoordinate()  to GameFundamentals.cpp

#define G 9.81 in GameFundamentals.h

Removed keyboard movement test from GameLoop.cpp

Added a vector holding pointers to player objects in GameLoop.h and a
method to add a player.

Removed angular components from GameObject
Changed _frictionLinear to _frictionForceMagnitude
Updated GameObject::applyForce(...)
Added GameObject::animate(float)
Added GameObject::move(...)

Added unit test for VectorQuantity::getAngle()