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.
Since these are really just data structures they belon in the common library. Also,
it stands to reason that we'll want to reuse them in other components, such as the
result handler.
Fixes bug in backtest history provider
Requests for bar counts were always incorrect because the history provider
was emitting bars whose end time is equal to the start time.
Implemented a FilterEnumerator<T> privately so he can filter those out
when using non-tick data
Stefano Raggi