Changed the implementation of the Gating-ML 2.0 ASinH transformation calculation

Changed the implementation of the Gating-ML 2.0 ASinH transformation calculation.
The previous 'direct' implementation seems to work just fine for me; however, Wayne Moore suggested, that this calculation is be more stable. It is giving the same results based on my tests, but I switched to it just in case there are actually cases, where this is preferred over the direct implementation because of some calculation precision issues.