Explicit hydrogens invert winding.
Improved winding detection for tetrahedral centres.
Improved identification of tetrahedral elements. More improvements needed but now any non-planar bonds indicate a tetrahedral centre should be created in 2D depictions. In 3D depictions, we check the environment of each neighbour. The method is currently inadequant and fails to identifier interdependent stereocentres (as seen in test) but is required to avoid create tetrahedral configurations for non-stereogenic atoms (i.e. methane).