Improved the calculation algorithm. The zero line crossover is now checked after a bar is closed.

Сode optimization

Improved notification of divergence, of crossing the zero line.

Added input parameters:
- Calculated bars - to optimize calculations;
- Arrows displacement - for placing arrows conveniently;
- Line bull divergence color, Line bear divergence color - color of the divergence lines.

Added the possibility to set up alerts for divergence and zero line crossing separately. Additional input parameters:
- Display divergence alert (true on default);
- Display cross zero alert (true on default).