[BUILD] Randomization script refactoring

1) Refactored randomization logic to the top
2) Add logics to support window platforms
Search: Added support for named filters/queries inside nested filters and queries.

Closes #6293
Query: When parent doc is found stop iterating over segments and continue with the next top matching child doc.

The parent doc has been found and there is no need to check subsequent segments.

Closes #6895
Closes #1843
Scripting: Remove setNextScore in SearchScript.

While it would be nice to do this all the way up the chain (into
score functions), this at least removes the weird dual
setNextScore/setScorer for SearchScripts.

closes #6864
Scripts: Make ScoreAccessor utility available for other script engines.

With the removal of setNextScore in #6864, script engines must use
the Scorer to find the score of a document.  The DocLookup is updated
appropriately to do this, but most script engines require a Number to be
bound for numeric variables.  Groovy already had an encapsulation for
this funtionality, and this moves it out to be shared with other script
engines.

closes #6898