This method is misleading at best and incorrect at worst.
Insight objects should use reference equality or compare ids to
perform equality checking. The only usage, in MacdAlphaModel,
was easily converted to not relying on this method.
Buying power model's GetMaximumOrderQuantityForTargetValue returns the
delta quantity needed to reach a particular position, so we need add
back in the existing quantity to get the total quantity required.
The term 'alpha' is used to describe the entire algorithm. Therefore, 'alpha'
produces insights. From this we have things like IAlphaModel, which is the model
defining how insights are produced. We have IAlphaHandler, which defines how the
insights from a single 'alpha' (the algorithm) are managed, analyzed, and stored.
Types closer to the individual prediction level, such as InsightDirection, or
InsightScore relate directly to exactly 1 insight. The distinction between the
two became more clear as we developed the insights API, and from that effort it
was decided to harmonize alpha/insight terminology across the various QC systems.