Reflections table column addition

[gustafsonsven]

The reflections table currently has intensity information for powder via Ip (powder intensity), however, there is no HEDM equivalent to work with. Adding a column which combines structure factor, polarization factor, and Lorentz factor together (specifically (|F|^2)(polarization)(Lorentz)). This is already taken care of in the powder intensity calculation (along with other factors). Such a value would also be a more useful value when filtering HKLs in fitgrains. Thoughts?