1.19.1

Minor indicator updates:

• added more parameters to Stochastic Oscillator for customization of KDJ - #621
• added initialFactor parameter to Parabolic SAR - #619
• added SMMA option for Moving Average Envelopes - #617

Minor bugs fixed:

• improper lines when ZigZag has not met the threshold - #618
• special exception to Parabolic SAR values during reversal - #620

Special thanks to:

• @kokazani for encouraging added KDJ customization
• @Salardx for providing data for ZigZag that uncovered an unusual error case
• @overstartup for recommending initialFactor for Parabolic SAR