WaveTrend Oscillator [SystemAlpha]

This is a WaveTrend oscillator enhanced with:

- Customizable Overbought and Oversold Levels
- Option to use Heikin Ashi for calculations
- Show WT and Signal Only or Histogram Only or Both
- Show Buy and Sell Alert - WT Cross
- Show Bar Color
- Use Overbought/Oversold Filter - Avoid buying at overbought and selling when oversold.
- Show Reversal alerts only
- Show Regular and Hidden divergence for either the WT or histogram
- Show Divergence Labels
- Generate Buy/Sell and Divergence Alerts