Expose certain PP5 context properties in PP5EnrollTransform

@JordanCheney @mmtaborsky While the default PP5 settings are good for getting the maximum recognition performance under all conditions, they are non-ideal when enrollment speed is a concern. This PR allows certain context properties to be set in the algorithm string that are particularly relevant for changing the speed/accuracy tradeoff.
Is there a way we can let people know that this value is the natural log of the IPD? so if you want an IPD of 40 pixels you would need to set this to ln(40). Otherwise looks good to me :)